Paizo the people behind our Cauldron adventures have been working on a sort of open source upgrade to 3.5 as an alternative to WOTC's 4th edition. The idea is to refine the rules but still be able to use the vast array of 3.5 material out there. I guess they really didn't like what WOTC were doing with v4.
The final version is not out until next year but they've just published the Beta version in hardback or as a free PDF if you register on their site. Only 400 odd pages to stare at on your PC/Laptop.
http://paizo.com/pathfinderRPG
