Dropbox offering 5GB free?

Sorry for posting this here, but I know many apple users are using Dropbox.

With the Skydrive launch and all the Verge coverage on the subject I keep reading about Dropbox offering 5GB storage. I've been using Dropbox for some time now, but I only have 2GB...

How can I get the 5GB? No referrals please, I hate to be spammed so I don't spam others either :)