Final Verdict:
The bad: Leveling Scheme and leveled equipment and leveled enemies suck. Attack magic is lacking in variety, and has graphical effects severly lacking. Horses border on useless.
The good: Mods can fix everything about the level approach, from the need to mathematically plan out levels to get max bonus to the screw over if you do quests too soon. Dark Brotherhood quests especially, but actually most quests, are well done. Melee combat is lively, and stealth is very well done.
The ugly: The interface. I really, really, REALLY hope the upcoming patch is doing something to de x-boxify the PC interface, and add in functions like the hold down shift to sell all at once and avoid annoying confirm messages, spell book spell deletion, more hotkeys, a way to bind the mousewheel to change through hotkeyed equipment, a way to bind keys directly to a page of the main menu screens instead of having to go quest screen->map all the time.