Seeing all the people who love DIablo 3 baffles me, because I get nothing from those games. Most people who love it seem to love the feeling of progression, hot new loot and leveling up. I don't really care about that stuff. It then struck me, what is absolutely core to the gaming experience can be radically different from one person to the next, which is kind of freaky no?

For me I would say immersion is what is core to my gaming enjoyment. I like being immersed in crazy worlds and feeling in the moment, ready to turn that corner or walk into that wasteland. Feeling like "I'm there" and not in the real world is what I love about games. Story helps with that, but only when presented in an immersive way, i.e. no paragraphs of exposition without context (looking at you Betrayal at Krondor).

So, progression and immersion seem to be two different core gaming needs... what are the others? What is yours?

My desire is to be able to play all these new-fangled games :(

When I thought of what was most important to me about gaming, what really got me excited, immersion was a quick decision.

COMPLETION!

Complete control over my game content, free of DRM.
A complete experience with all expansions and DLC.
Completing games.

Hmm. Not sure. Entertainment is the largest one, off course, the worst thing a game can do is bore me.

As mechanics? I like to explore and experiment, so freedom is a biggie. Progression, also possibly, but maybe more on the side of experimentation, I think. Immersion is also important, but for me it is a matter of consistency - for me a game will have some immersion as long as it is consistent

(but I hate breaking the forth wall... I do not like being pointed out that I am playing a game in the middle of the game. Very few games manage to pull it off)

I can't say I have one core gaming desire - I am too changeable - it will depend no my mood at the time.

Generally immersion is in there but, more recently, I love to see how games have developed over the years since I've been playing them so damned long.

That works both ways - seeing the advance of technology in new games is amazing - but also looking back and seeing how much was done with so little resources in older games. I think that comes from being a software engineer - knowing how its done doesn't remove the wonder of it.

But then sometime - just the sheer, almost primal, fun!

I don't mind progression provided that it's not overly linear.

The more it gives me the feeling that the current path is unique to my decision making (or at least requires some serious head scratching) and hard to replicate (whether is character progression, city building or something else), the happier I am with the experience.

In essence, creativity is king.

Failing that, immersion (racing, shooter, good puzzle game, RPG with a very engaging story and setting) works too.

It really depends on the genre.
I enjoy a challenge, so I love games that challenge me. However, I will hate the game if the challenge turns into trial & error and frustration. Therefore the game must have solid mechanics.

How to do it:
Diablo III - great, great balance. Will see some patching / hotfixing to truly refine it, but yes, the progress and the challenge are a ton of fun. The game also has great depth. In terms of mechanics, that is. The story is shallow, but then again, I played D2 fanatically for almost a decade and I'm still not sure as to what the story is about.
CS 1.6 - the best MP shooter ever made. Enough said. Simply an amazing game in terms of refinement.

How not to do it:
CoD:MW3 - linear levels. The game's idea of a challenge is to throw as many enemies at you as possible while you move from checkpoint to checkpoint. It's an utter bore. I loved Spec Ops in MW2, it had some interesting and diverse levels, most of which required different approaches and decisions. I.e. the Sniper level. Maybe 30 enemies in total in that one and I think the first time I finished it on Veteran it took me ~15min.
In the average Spec Ops mission in MW3 you will have to plow through 100-300 enemies. It sucks.

Different factors for different genres though.

I guess this is a bit similar question as the previous "which is more important to you in games, story or challenge?". I consider "story" be a similar element in a game as e.g the music, ie. it can make the game more enjoyable, but it is hardly ever the main reason I want to play a certain game. Or if it is, then at least I don't consider such game to have any real replay value, and frankly such games would give me about as much enjoyment if I watched someone else playing them (e.g. longplay videos in Youtube) instead of playing them myself.

As for Diablo series, Diablo 1-2 felt ok to me overall, but that's all. Diablo 2 (single-player) became considerably more interesting to me when I learned properly how to use the transmute box, and I got a clear incentive to find ingredients to make e.g. the Prism Amulet.

I don't know how much Diablo 3 is alike its predecessors. If the gameplay is toned down (e.g. autoleveling etc.), then I presume I'd find it even less interesting than 1-2.

An emotional connection or great narrative conveyed by purely interactive means. This is one key thing I am looking for in a video game as of late. The only game that has done this recently is Journey.

I've been watching many more films as of late, I am pretty disappointed at how lacking games are in comparison in terms of writing, depth and originality. If games are going to have cutscenes and ape movies, they had better tell an interesting story or ape GOOD movies. For 99.9% of the time, they don't.

I don't really play video games anymore, I have found movies to be a far more enriching and enjoyable experience. There's one game I'm looking forward to this year, Persona 4 for PSV.

I don't have a problem immersing myself in pretty much anything. Pure shooters (which I don't play a lot) are probably the best for that, since you just don't have time to think about anything but the game world, and because their interface is mapped to a simple understanding of the real world (first person with easy movement).

I probably enjoy stories more, though, which is why I prefer RPG's and adventure games. I also enjoy minor challenges. I want to have some challenge, but easy enough that it won't stop my progress. I enjoy being made to think, without being punished for not thinking well enough.

In general terms I appreciate detail and control. I don't like having control taken away from me. Which is why I backed Takedown and why I don't appreciate the direction CoD and its clones have gone.

Detail can come in many forms, such as the story, gameplay and even the graphics. For instance, one of the things that I loved about Deus Ex's Hong Kong section was the sheer attention to detail there.

Both detail and control factor into open world games, which again might explain why I enjoy them more than linear games.

This is probably why I rank the Stalker games so highly. The level of detail and control there is practically unrivalled without going into sim territory.

My core gaming desire is just to have fun.

Depending on my mood, I can have just as much fun playing a mindless hack & slash game as I can have playing a cerebral adventure game.

I suppose one key ingredient to my enjoyment of a game is stability & convenience. So if a game is generally bug free and I can play it whenever I want to, I'm pretty happy.

EDIT: typos

Coincidentally, I was just about the mention "The Journey" as one such game that I see no reason to play myself, after watching the longplay video from Youtube (ie. watching someone else play it). I could be wrong of course, but I felt that there wasn't really that much to "play" in that game, besides finding the next hotspot and performing some simple action there to proceed with the "experience".

Somehow, that sounds fitting, if you are mostly looking for a "movielike experience" from videogames. I guess real movies will always do that the best.