Regarding fan outrage taking the form of death threats and other violence here's Devin Faraci, reporting at Badass Digest yesterday:

Rotten Tomatoes was forced to go to tweet a reminder that any commenters who broke their basic terms of service (which I'm sure include things like 'Don't make death threats') would be banned from the site. That they would feel the need to do this only hours after the first negative reviews hit shows the force of the onslaught. There are thousands of hate comments still standing, with many having been deleted by a surely overworked moderator.

Since originally posting, he's issued an update that Rotten Tomatoes has disabled commenting in advance of instituting a Facebook-backed, anti-anonymity system.

It's terrible that fandom has devolved into this sort of statistic-obsession, rather than the fandom-positive nature it once had.