Yes and no.
I love coming up with stories, ideas for encounters, and reacting to the players' actions from the previous session. I'd go so far as to say that I enjoy doing that more than actually running the game itself, which is why I almost never use adventures written by other people (whether it's a module, PDF, Dungeon magazine, etc.).
I hate statting out monsters and NPCs, especially spellcasting foes. Even with a wonderful program like E-Tools, it takes all night to come up with a spell list and plan of attack. If I don't plan their attacks out beforehand, the combats take 2-3 times as long.
I think that's the real reason I hate running high-level games. It takes longer to prep for a session than it does to play it.
A lot of times, I will just cop out and pull the stats straight out of a monster manual or other source. So I put "yes" as my final answer.