Does Playing in a New Genre Revive That First Time Feeling?
I've all but dumped traditional dungeon fantasy in favor of other genres for precisely that reason. I still get the thrill of possibility from sci-fi, modern, and post-apocalypse games, whereas that train left the fantasy station long ago.
To be fair, though, I do still get that thrill if I delve off into a completely new system or completely new group of players, so long as it's not Yet Another D&D Clone, but actually brings something special to the table.