I'm glad I've not experienced the boredom some of you have. Despite over 400 hours of game time, I've yet to come close to feeling bored of the game (and this is with horse traveling 90% of the time). With so many quests open, I do feel inundated with the tasks, but I made a promise to these people I'd help them find a mammoth tusk, a bracelet, a sword, a helmet, and other items they've lost and are too scared to get on their own.
Dang it, that's just the kind of Khajiit I am!

After I completed Obvlion, at 726 hours, I felt sad the game was over. I hate post-game depression.