Well, looks like I agree with IGN a lot of the time, because I think Iron Man 3 and The Dark Knight Rises are MUCH better movies than The Amazing Spider-Man. IGN hit the nail on the head with their ASM review, in my opinion.
As for critics and "The Tomatometer," I'm predicting it's going to be a mixed reaction, leaning more on the "fresh" side. I'm thinking in the 65% range from critics? Only reason why I'm saying this is because the movie looks like it's pulling a Spider-Man 3 with all of these characters and villains. Plus, dropping MJ and adding someone else to the cast isn't necessarily a good sign for me. Looks like they're having to rework/revise a lot of things in the script on the spot.
As for the fans, I can't predict what they're going to think at all. Fans tend to cherry pick what they classify as a good comic book movie (myself included). TDKR got overall glowing reviews, with a mixed reaction from fans. Iron Man 3 got good reviews, with a mixed reaction from fans. Batman Begins (back in '05) got a mixed response from critics, but fans to this day consider it to be one of the best in the genre. Watchmen got a mixed response from critics, but an overall positive response from fans.
So. Yeah. Hell if I know.