One big reaason is that game companies now focus on the big gaming convention trailer instead of the gaming walkthrough. You can't showcase this amazing level design in a 3 minute trailer that has to blow everyone away. One thing though, for me, a detailed, really big system of level design can be annoying as fuck. For example, since they are mentioning here Jedi Knight, I've been playing the Raven jedi knight games, Jedi Outcast, which has this big, confusing array of tunnels, vents, secret areas, and such. There's nothing more annoying to me than thinking im going the right direction, because I'm running areas I hadnt seen before in the level, only to jump down thru a vent and fall right in the room I started the level on. There has to be some kind of direction where to go, in my opinion..

I always wonder why they don't sometimes literally signpost directions for the player.
In some games, you're in places where the staff would need to know where to go... so it would be totally in keeping with a certain level of realism to have a conventional layout with appropriate visual cues to get the player where they need to go.
Half Life 2 and Alpha Protocol both had sections where it seemed obvious which way to go through various sorts of visual cues. If you actually try and search around you can see where it's blocked off, but it does give the illusion of being in a larger space.

Yes and no. Depends on how combat heavy the game is. Constant battles like Serious Sam (Extreme example.) can get away with a linear approach but if you start adding other stuff like character development where you get skills that for example make you jump longer/higher go well with big maze levels with more than one solution. Non linear that is.

I really find it interesting how so many people, here and on the PC Gamer forum, just find it instantly frustrating and annoying to not know where to go.

Not really if you look at entertainment products as a whole.
Films is a good example. It's getting harder to get success with a slower film that have build up for the kicks than a film with slow parts of being cool and mostly kicks. It's the same trend everywhere. Everything is going faster and people don't want to have to do much to get kicks. It's like sitting in front of the TV with 50 channels and zapping through them to get to something you like instead of sticking with the program you're watching and actually pay attention to get to the good parts of the show that you can't see in 5 minutes.
"Entertain me. Now"

It wasn't so annoying when I had more than an hour a day to play games. Now it's just a waste of time when I end up going in circles because some dev hasn't heard of proper level design.

It's fine if you don't have the time, patience or taste for it, but it's not bad level design, just different goals. Like I said, the designers of Jedi Knight could have made it a linear corridor, it would have been easier to do so. At that time the objectives and path finding was part of the experience.

I don't remember how Dark Forces 2 was (it's been a loooong time since I played it), but I think pretty much everyone can admit that Jedi Outcast, while it had an awesome multiplayer, had some pretty abysmal single player level design (Nar Shadaa anyone?).

Hate linear gameplay, will stick to shit like Far Cry.

Been a bit too, but if I recall correctly, DF2 was almost a textbook example of a transition game. The maps were still built as though we needed to go on a key/button hunt, but the gameplay itself was pretty linear. So (on some maps, the levels leading up to the Valley come to mind) it was pretty easy to get lost, but you were never really looking for anything.
And yeah, JK2 had GREAT gameplay, piss-poor level design :p

When I was younger, I had horrible times figuring out where to go, what to do, and/or the general difficulty of older games. Now, I'm almost 30 and find I can enjoy all those old "hard" games.
What I still hate a bit, is hunting for pixels in some old adventure game. That, and MYST.

Agreed with the OP. Personally I feel the only think Bioshock was missing was a little more freedom of exploration.
*VERY MINOR BIOSHOCK SPOILERS*
(Of course, without too many spoilers, there was a reason for that in the first half of the game, but after that, they should have made it more open for contrast. )
*END*
Probably my two favorite FPS games of all time are Jedi Knight 1 and Terminator: Future shock. Both had a great balance between Openness and Focus. IMHO that was the golden time for FPS level design. The developers were forced to work with certain graphical limitations - and, as is often the case, that forced them to be great.
FPS games these days have amazing worlds, they often feel very real, they have great weight and atmosphere, they have amazing set pieces, pacing, sense of scale and gunplay. But the level design is usually pretty poor.
I think level design has become a lost art. It used to take a lot of skill to make an effective level within the limitations of the engine - these days I get the sense that the level design is the artist's world design. There are no more celebrity level designers! ;-)
I can't say I miss being totally lost, but I do miss the feeling of exploration, environmental puzzle solving, freedom, and "how the hell do i get up there?!".
The great thing about Jedi Knight was that the balance between freedom and linearity was just right. You were never lost, you were just working out how to get somewhere. (or stuck on an environmental puzzle).
Future Shock somehow managed to have levels that were outdoor wastelands full of rubble and destroyed buildings - you had total freedom of direction, yet you always ended up in the right place. They used lots of subtle cues like the landscape, the location of fires, enemies and elements of interest to always draw you towards the right place. That took skill imho.
It's also worth pointing out that FPS games are almost entirely 2d these days, there's almost no verticality. Is that because of the limitations of console controllers? Quake, and especially jedi knight seemed much more vertical. Even Duke Nukem!

That's a good summary for the thread, I tend to be too verbose. I miss those moments in shooters terribly, none of them have that anymore. Bioshock had a bit of exploration, but no real feeling like you needed to discover a route or how to get to something. No other FPS games even try anymore.

JK1 is definitely one of my favorites as well. I recall having played a demo of Future Shock back in the day and quite enjoying it. Maybe I'll hunt on eBay for a copy of that.