I liked the organization of the menu systems and my XBOX version (love the couch!) is very stable - I was actually surprised since this is Bethesda's inaugeral game engine. Very impressed with the graphics and overall system.
But there were 3 things I didn't like, felt like they poured bleach on parts of the UI:
1. I didn't like the fact they removed the spell effect display from the main UI window, unless I'm missing it somehow. I do see it updating for shouts but not spells. For example, when I cast a conjuration spell, I can't tell how long I have until the spell is over. In Oblivion, it would appear in the top right, and it would display all your spell effects if you had multiple spells or effects going at once (like if I was hit with a drain strength spell, I knew to cast a dispel magic spell). That was nice since I could pace my spell usage to prepare to summon another critter, or how long my oakflesh would last. I understand their is a glow around your body for Oakflesh and can hear the summoned creature disappear, but when you are in the thick of battle and looking at a 2D TV monitor, it's nice to have those visual aids since you don't have the same benefits as if you were really there, which pulling those systems is trying to achieve. I understand trying to push realism, but I'm NOT THERE. I'm using a controller and a 2D screen that pulls in only about 1/5 of the screen at best. I need the visual aids!
2. Also, in Oblivion, I liked that I could go into a quest and see what the dialogue was around it. Sometimes I would forget what was said, then I could go back and get some clues or hints about what needed to be done or just understand the quest better. In the new system, it just says, "Retrieve the Staff". Since I sometimes bounce around between quests as their are hundreds, it was nice to have that thread to come back to. For the most part it's not that big of a deal, and I can consult the strategy guide, but wish they maintained some of the background like before, made it more meaningful.
3. Not a big fan of the perk system. Because of how this particular perk system works (especially with 0/5, 1/5, etc and the semi-infinite leveling system) they had to strip out everything and then some from the system to start out so you would have enough to last. You get ONE perk point each level up to get what I consider to be the basics back into your game. According to their strategy guide there is no limit to the level you can acheive, so I think they were hoping to pace themselves up to level 100 with enough perks to last that long. To me that means a TON of nickle and diming this important system. Also because of the perk system, they had to trash their extensive spell list and spell creation (understanably), but loved that system much, MUCH better. The harp on the fact that they want you to have a custom experience (ie. no XP points, all based on your skills that you use during the game), but then they strip out the best custom experience in my opinion which was the creative spells making (half of the combat system).
Here comes PR boy...