Here's a small list. I'm sure nearly all will agree.
1.More action. Morrowind felt boring after a bit, like the RPG system just leaked out to you, calculating your fate, in Oblivion, everything is made so you'll want to do it again. No more stand still fights, there's ducking and weaving to be done, stealth is exciting now, as you perfrom stealth attacks, magic is thrilling, I will enjoy blowing monsters away, short circuiting them, and converting small rooms into a freezer.
As a theif, you sneak in the night, kill someone, drag their body away from gaurds, jump up some boxes, across a roof, drop into an alley, sneak away, that kind of thing.
If you go beserk in a tavern, guards will flood through the doors, some people will sneak away, others will defend themselves/others, you'll be knocking people left and right, items flying off the tables.
Mage? You wander as a necromancer, shocking that last bit of life out of someone, only to raise them again to do your bidding, or perhaps you are a kind man who heals the wounded soldiers protecting an attack from Oblvion.
It's this kind of thing that hooks me, the action makes you feel more involved with the world.
2.Looks beatiful. Eroded soil, tall grass, trees shaking in the wind, double levels skies above, wander into a crypt, dark and muggy, chains hanging, skeletons creeping, great ambience all around.
3.Features. You've just defeated a powerful necromancer, you leave the cave you were in, get on your horse, ride to the village you are living in, shop around, go to the tavern to hear a few rumors, head home, place your precious newfound artifacts on a table, and rest in your bed that night. You wake up the day after, ride to the arena, earn some septims showing your strength, and ride out following a rumor of nearby vampires.
In Morrowind, you were a homeless man, who didn't have any friends. In Oblivion, you own a few houses, do some freelance work, and gather your artifacts in your house.
4.Better balance. I feel the RPG system is not only there, but it is improved. I fail to see the need of some skills you train to acheive in, but find out they are practically worthless later on. With Oblivion, you get 7 skills as Main skills, and 14 as Misc skills. This let's you amek a character with any skills, and he'll still be good. I could take Athletics, Hand-to-Hand, Armorer, Alchemy, Acrobatics, Mercantile, and Speechcraft, probably the most useless combination, but then I'd just become a Monk tradesmen by accident. With Alch, Merc, Speech, and Arm, I save tons of money, so I can buy really good equipment, which would let me train one of the two armor types easily, And Acro, Ath, and Hand-to-Hand means I fight like a butterfly, sting like a bee. Not to mention Speechcraft's ability to get what you want from people.
5.Finally, the AI. No doubt here, the AI is several times better. now they follow you through cells (doors), get around objects easily, others assist them, some flee in terror, others still will trick you, and you can find new ways to trick them. Good stuff...
Summary: Good job Bethesda, I loved Morrowind, and I'll surely love this game 10x as much, even with my weak PC. smile.gif Hopefully, I'll get a new PC by the end of the year to play this game well.