Here's the scenario I'm worried about. But first, my assumptions:
I'm guessing that Hasbro indicated to WotC what their revenue expectations were. WotC did market research, conducted informal polls, tested out different strategies, and decided that the only way to meet these targets was to have product that sold like the core books. Okay, so they do a revision.
Now what happens next year, and the year after. Presumably the pressure from the parent company will continue, and there will always be the 'easy out' of doing a revision provided enough time has passed. If you know you're going to get another chance to fix things that get messed up a couple of year down the road you'll be more likely to play around with things that may not have been completely broken.
I don't know how close to reality this is, or where the decisions get made, but I do know I don't want to buy another revised edition 3 years from now. I would also be unsupportive of products put out to sell extra crunch to gamers at the expense of system integrity. Oh well, if things really go off the rails we'll always have the SRD.