There are things in 3.5e that irritate me (Turn Undead, Metamagic, etc.) and I'm looking forward to the next version of those abilities; however, 3.5e will be good for several years of play yet.
If the fabled 4th ed. is released in the next couple of years, I won't be buying it. I've got way too many good 3.5 books! 3.5 is an excellent game, and I'll be happy to play it for many years to come.