DrWevil: I do. A well written, fair point.
Personally I'd still rather be playing the game over watching someone else do it (in its entirety anyway) but I can see where you're coming from more clearly now. In one sense, you remove the required interactivity but still allow the user to follow the game. Making it more like a book or film. I can see how a game as well written as Arcanum could lend itself to that very successfully.
In another sense, my assumptions were correct about it being used as a walkthrough, following how somebody else has played the game, whether for problem solving, inspiration or just entertainment. All perfectly valid reasons and I'd guess a lot more intuitive than reading through a block of text.
I was just curious to find out if I was missing something, like a set goal of some kind. As the only full-game video run throughs I'd come across tended to be speed runs which focused on exploits or glitches to beat the game quickly.

Mnemon: I generally prefer Let's Plays in written format and by people that know the game well. Think they serve a variety of purpose ranging from information to entertainment. In a way, a well written Let's Play, can work as a demo, an introduction and tutorial to the game elements (this is particularly helpful if the person writing it knows the game well. There might be aspects of the game you just don't notice as a newcomer). It might reveal approaches to the game you'd never have come up by yourself, either.
Let's plays can introduce you to games you never heard of, either. [And a good number you probably never want to play, after seeing what they are about :) ] A good number are actually also quite interactive (again written ones tend to be more so, than video versions] as they are usually posted on forums in instalments and readers get to make some choices on key decisions along the way.
The biggest part though, in a really well written Let's Play, is humour. And this is also the main reason why I don't like the video versions that much. In video versions the writer's creativity is tied down by too many constraints. A video segment can only be so and so long, the game has it's own pacing which might not be good pacing for the type of sarcastic/funny/smarmy comment the person playing might attempt to set up.
Some LPs I like:
Let's play ...
*** Tie Fighter ... from memory ... with heavy influence from the readers.
*** Animal Crossing
*** Medieval II: Total War - as a Scottsman in Egypt.
*** Wizardy 4 on "ironman" difficulty (game ends when character dies, no re-loads).

Raberdeen: I wanted to thank you for creating and posting these videos. I recently bought the game, and found myself a little lost. Believe it or not, I've found your videos quite helpful and I learned a few things from watching.
Thanks again.