Title says it all. I really enjoy the spell-making. I've spent all my money on making as much spells as my wealth could give me, and I don't regret it. I really wish they kept that in Skyrim. So what's your favorite Oblivion mechanic?

Attributes. Boy, do I miss Attributes.

Acrobatics. I like the awesome jumping you can do in Oblivion. And of course spell-making.