I'm sick of listening to people whinge about how this plot twist is something they did not approve of and they are offended because they did not approve of it.
Marvel is planning to do this, "If Spider-Man were Batman" storyline for atleast a year, if not longer. It will not be permanent.
I'm aware of a lot of the twists an turns over the character over the years, even the time when he sold out and got a corporate sponsor, which led to the Spider Buggy creation. This one struck me as not a big freaking deal either.
At best it's a second act plot twist of a much longer plot. At worse, it's semi permanent and Spider-Man will have a Jeckyl and Hyde persona to deal with. Actually, that last one I want to see.