This year, Worldcon will be Chicon 7, because it's being held in Chicago, IL. I won't be heading to Chicago in August, but I did buy a supporting membership to Chicon. If you want to know one big part of my reasons, take a look at this list of Hugo nominations for 2012, just announced today.
There are 5 novels, 6 novellas, 5 novelettes, and 5 short stories nominated, as well as several works of nonfiction and some screenplays. As a member of Chicon, I get to vote for the Hugos; to help voting members decide how to vote, Chicon will send them each a digital packet of pretty much all the nominated works, all 5 novels, all 6 novellas. etc. The last couple of years, they've been very good about providing a variety of formats, so putting these works on an ereader is pretty easy.
It's a lot of stuff! My usual plan of attack is to read the shorter works all the way through. With the novels, if it holds my interest, I finish it. If it doesn't, I move on. But when I get my ballot, I have a pretty good idea how I want to vote, and I feel much better about picking one work over another because I've at least started everything.
If you're interested, check out the online registration page. Supporting memberships are still $50. But don't put it off, because you'll need time to read all those works in time to vote!