Spider-Man 3 and Batman and Robin were very poor films, so the idea of a reboot was more warmly welcomed. I don't think fans will be as glad to see the back of the established order this time round.
Personally, I'm used to the idea of different Batman continuities so I'm not too bothered. Film has never been the ideal medium for superhero storytelling anyway, as it loses the long-term arc storytelling. A huge reason I'm a fan of the genre in the first place.
I recongnise I'm one of the few people who like Spider-Man 3 (and X-Men 3) but were people really clamoring for Amazing Spider-Man? I remember their being rumors about a SM4, and people didn't seem to upset that the Spider-man movies would continue, even after SM3.
I'm actually not against the concept of reboots for movies. Eventually, actors will want to move on or just get too old for the roles, or the series would just become stale. I just don't like bad reboots. I won't get into some rant, I'll just say that, with Spider-Man, I was extremely dissappointed in the Amazing Spider-Man. ASM is in no way any better than SM3, its actually significantly worse, and has a main character whose acting wouldn't be acceptable in a SyFy tv movie. I still crack up trying to see that guy "act" at being sad when uncle ben died, its simultaneously the funniest and most pathetic piece of acting i've seen in a high budget movie.
But, I actually went into that movie with an open mind. I knew I'd miss the old guys, but I was willing to see how the new guys would do. I did the same thing with batman begins. Of all the things I can (and have) complained about in superhero movies, the idea of a reboot has never bothered me. Reboots can be fine, I just wish they'd actually improve on what they're rebooting, or atleast match it in quality (assuming the thing its rebooting was good to begin with, atleast at one time)
Its also preferable not to do a straight up origin movie if you've already had one that people still remember, but I can handle an origin if its done well or different enough from the one before it (in execution if not in the basic story). I'm more than fine with a Batman reboot, I actually wish it was a real, full reboot. Let someone who has never written a Batman movie write him, not the guy who helped write the last version of him. This new batman won't be a real reboot, more like a tweak to fit with Superman's universe. I'm assuming he'll be Bale's Batman, just without Bale and with a tweaked backstory so that he fits better in a world with Superman. I'd wish for more of a reboot, but they will want to make sure he's the same Batman Nolan did, so that they can bring in more money. Maybe in a decade we;ll see a real Batman reboot, but it won't be in the Superman/Batman movie.