crime became more newsworthy. A violent mugging a day wouldn't get reported, while one a month would make the front page. Perspective vs reality.
You can look at the article you posted in different ways too. Someone pro-gun would say "Gun control is irrelevant to gun crime" while someone who was pro gun control would say "Gun crime is down, so do you really need so many guns to protect yourself?" Ultimately I think that 11000 murders a year, at a rate higher than any developed country is still a big problem, no matter how you slice it.
Speaking of different perspectives, there were some interesting stats released a while ago that basically said gun murder victims were more likely to be black and young while suicide victims were overwhelmingly older and white. Since they pay different costs from living in a society with lots of guns - African Americans being more likely to die while young, and white Americans more likely to not be affected by gun violence until they are older - they have different perspectives on gun control. Here's one article (from a conservative commentator) about it if you want more info:
http://www.cnn.com/2013/01/15/opinion/frum-guns-race/index.html?c=&page=1