Aside from the brown/gray problem, I've noticed that lots of current-gen games have really boring environments. I've been seeing more and more variations on the "urban" theme; 1940's, near future, distant future, most of which have a bunch of ruined buildings. The huge crop of FPS/3rd person shooters is just littered with this type of thing.
Why? Is this kind of environment easier to make look "real"? There are so many games now that have "real" environments as opposed to fantasy-type settings that really look weird and cool. Look at MDK 2 for instance. That game had so many goddam cool looking areas. Even Hawkins' ship had a unique "retro-future" look to it, with 60's decor coupled with futuristic things.
Of the top of my head, I'd think the Metroid series might have some potential to pull off things like this, but no. Most current Metroid environments are really generic. You've got your metallic spacy corridors, and then you go outside into a jungle, lava pit, snowy area, blah blah. I can't even tell which Metroid game is which by looking at screenshots.
Metroid Prime screenshots
Metroid Prime 2
Metroid Prime 3
If anything, the look has gotten worse over the series, which you can clearly see heading down the "same thing as the last game, but with more brown" road.
The modern gen games I've played:
God of War 3: Yeah, realistic Greek temples. Seen it.
DMC 4: A castle, a snow area, a forest, rather boring. (DMC 1's castle was really creepy. DMC 4's just looks dead.)
Demon's Souls: Another garden variety of mostly "real" environments.
Dante's Inferno: This probably has the most interesting environment to it, as it's someone's vision of Hell, with things like walls of coffins containing live (dead?) souls, people entrapped in climbable walls, and the golden area representing greed (why does Hell have an ice bridge though?). But the neat looking areas are more the exception to the norm, and they're still coupled by rocky hallways.
So why are developers so obsessed with "real" as opposed to more fantasy environments? Because you can look at a real environment and have a point of reference, something you can't nevessarily do with a fantasy environment? "Why yes, that does look exactly how a damaged skyscraper would look.") Because developers are copying each other and are no longer being creative?