WotC has shown a big interest in pushing the boundries of 3.5, which I like. Despite the fact that someone labeled Dragon Magic as forgettable above (*sob*), when we were designing the book we were encouraged to do new things, particularly with spells. One thing I really thought was fun were the "synergy buff" spells, which are suites of four spells that have extra effects when 2 or 4 of them are up on you at once. Anyways, point being, WotC is definitely encouraging us designers to think outside the box with nearly every aspect of the game.
I, too, like the reserve feats, and they're something I've been hoping to see for a while. Really, though, I wish I were playing a wizard instead of a sorcerer right now in one of my games, so I could use them!