Last year Notch gave all Minecon 2012 attendees a free Minecon-themed cape shown above. Just a few minutes ago Tobias Mollstam, the web tech guy at Mojang, announced that new Minecon 2012 capes will be going out to attendees now. He posted, "Just started sending out MINECON 2012 CAPES!!! Emails with links are being delivered to ticket owners (or buyer if none). Get that swag on!" On November 2nd Tobias said on Twitter, "Capes for MINECON attendees will be given when the event starts to have as a memory. They are pretty and blue." That means it will be different from last year's design seen above. If you have the new cape, send it in to us so we can post it!
Update: It seems this is the new cape. It is blue