...games for you?
I don't mean that you started mapping and suddenly you hate videogames. I mean, there is a certain bit of immersion that many games have that is at least partially broken for you.
Now, instead of paying attention to what the developer intended, I'm looking at details like how obvious it is that I'm actually just in a glorified hallway even though I'm outside, or how nicely detailed/not nicely detailed the world geometry is. I notice the one edge where the textures don't line up next to each other quite right in that one map corner that no one will ever look in anyway, I spot signs that some "surprise" scripted event is about to happen based on the way things are set up to bring the players attention to certain areas (albeit, this is more for older games where other restrictions in tech make it obvious something is going to move or break open or something).
The other day I played Starr Mazer: DSP for the first time and instead of just enjoying the beautiful pixel art passing by with depth in the background I was trying to see if I could count how many different parallax scrolling backgrounds there were (I do love me some good parallax backgrounds).
When I'm playing CS I'm constantly analyzing the way the layout is affecting gameplay and I'm nitpicking things as I see them (seriously though, some really good CS 1.6 maps have some terrible texture alignment sometimes). I'll be running though a building and get shot because I'm too distracted and bewildered as I sit there thinking, "I can tell you used CARVE! Noooo!"