Maybe I'm a bit crazy but.....
I have played using only Core Books for several years, dreading the explosion of Splatbooks I would be buying should I dare to pick some of them up.
However, with 4e around the corner, the release of 3.5 books is drying up.
And with that, I find myself buying more 3.5 books in the last two months than in the 3 years before that.
(also, the low dollar is helping. Shipping from america to the Netherlands included, it's still cheaper to buy them online than in the local bookstore.....)
My main problem is that some of them are getting hard to obtain.
I don't see myself switching to 4e any time soon. maybe 5th edition, considering I was playing Rules Cyclopedia D&D before 3rd edition, skipping AD&D entirely.....
so, I voted No.
Although I might check out Exalted at some time. For that matter, I'm also (irregularly) playing GURPS and Call of Chthulhu, so why not?
Herzog