The different resort classes follow different pricng schemes. For the value and moderate resorts, you ae in "regular"--not the best, not the worst, pricing, if you check in before May 23 (your price is defined by the day you check in.) It's "regular" all of May in the deluxe resorts.
It's been reported on this board that Star Wars weekend is up in the air this year...though I have also seen that it is invovled in one of the year of a million dreams sweepstakes. Don't have a date.
I camped in a tent at FW in early May this year, and the parks were great, as was the weather, excpet for one day and night that was very hot...