I just downloaded the Beta for the Pathfinder RPG and while I haven't read the whole thing I have to admit that I am blown away by the size of it. The main book is 410 pages and the download comes with an additional 65 page supplement. That is a a total of 475 pages of potentially free 3.75 material. This is also just the playtest material, not the finished game. I have to give Paizo kudos for pulling a stunt like this. They must be very sure of the quality of the game, and be interested in getting as many 3e gamers behind it as possible to make that much free material available. That is how you promote a product! Gamers love free stuff.
Like I said I haven't finished reading it, actually I've just begun, but I will be posting my thoughts once I am done. Paizo made the download for this product free to anyone who is interested. Granted the print version will cost you, but even that price ($24.99) is still cheaper than most gaming products.