I was wondering if I could vote for my pizza ?

I would not do that, but there are no usernames written under each pizza images so...
Maybe it's not a bad idea to think about making small change of rules for the next year competition.
Isn't that something every politician does in every election? I wouldn't do it.
Only difference that voting is done in private way behind the curtain, while in Bitcointalk Pizza Day you have to vote publicly
