I thought that Bethesda did a good job with the environmental aesthetics and I didn't feel that they departed too much from the original design in that area; my only complaint is the lack of those cool orange art deco doors from Fallout 1/2.
I thought they did a great job of that.
On the other hand I found their armor/creature/weapon designs out of place, most of them didn't really mesh with the 1950s comic book world that Black Isle was shooting for; most of them just looked too modern.
Also agreed here (sort of); Modern designs [IMO] are fine, they just need that 'pop 50's mind-set' to them. I'd have no problems with finding an http://i271.photobucket.com/albums/jj125/Gizmojunk/trpod.jpg player in the ruble (as long as it seemed appropriate).
Thats another thing, Fallout 3's art design felt too realistic for Fallout, something a little more comic bookish would have been very cool to see in full 3D like that.
I can't fully agree here, but I understand it. I would have preferred the ghouls look like the http://i271.photobucket.com/albums/jj125/Gizmojunk/compare-1.jpg, and not http://images1.wikia.nocookie.net/__cb20101229215018/fallout/images/8/85/Gob.jpg; but for the regular humans... Realism is good, [IMO] it needs only just a touch of the older "comic book" style. Think of http://i271.photobucket.com/albums/jj125/Gizmojunk/Aradesh-1.jpg, I think Obsidian did a good job of what I mean, in the http://i271.photobucket.com/albums/jj125/Gizmojunk/Aradesh2.jpg.
That's not to say that I'd not want to see a few http://i271.photobucket.com/albums/jj125/Gizmojunk/detailed.jpg in the mix...
As for actual 50's fashion and mannerisms... as though living in a time-capsule... (IE. Bee-hive hair and greasers...) I'd rather not see them at all; I'd rather see http://www.youtube.com/watch?v=R_SHozxzwqs, not a future idea of their past.