Canon just announced an upgraded Digital Rebel camera - looks like it'll have some nice improvements over the Rebel when it comes to shooting wakeboarding.
Major features are 8mp, 3fps, instant on, AI Servo focus mode (great for tracking a moving subject such as shooting a wakeboarder from a chase boat), smaller and lighter, black body standard, priced the same as the Digital Rebel.
http://www.dpreview.com/articles/canoneos350d/