I was wondering if I could vote for my pizza ? 
This should not only be allowed but strongly encouraged, despite looking not very honourable at first glance.If all participants were to cast a vote on their own pizza, that would even things out and would effectively have no impact.
But if voting on their own pizza is disallowed or frowned upon, then it discourages participants from voting at all (i.e. on other pizzas) as that would be acting against their interest.
Maybe for the next edition, we could have a rule that you can vote on your own pizza, but only if you also cast votes on other ones.
A quick analysis, there are 144 pizzas (users), each user must vote on 5 pizzas. Even if the pizza creator votes on your pizza, he will still select 4 more different pizzas. Voting for your pizza won't make things that different in the final result.
Furthermore, theoretically no one knows whose pizzas they are (I said theoretically). So, if a user votes for 5 pizzas, I can't tell if he voted for yours or not (theoretically speaking).
In short, I don't see a problem with everyone voting for their own pizza.
With my own assessment of voting dynamics (possible voting strategies), I was still o.k. with a contest participating member to vote for his own pizza while I was personally presuming that a member could vote for his own pizza and not vote for any other pizza. Accordingly, at this time a person could give all his voting weight to his own pizza and sacrifice his other 4 possible votes by voting only for his own pizza since there is no need for any voter to have to execute all 5 of his votes.
Personally, I don't have any problem with that.. .whether the votes were to be done publicly (which currently they are) or if they were to be done privately (which currently they are not).
Honestly most of the pizzas look pretty bad. No offense. But I can kind of imagine how they'd taste already and, nah I'm good.
I think this point somewhat relates to my earlier point about some of the relevance of the description of the ingredients and the process, even though surely there has not been any requirements that any of the participants give up their exact ingredients and/or secrets of the proportions... or the exact processes that might cause certain ingredients to take on a certain kind of flavor and/or texture.
Participants have been electing how much of their process and/or ingredients that they would like to describe, perhaps for the purpose of sharing the ability for others to replicate their results or perhaps for the purpose of garnering votes by appealing to some of the open source inclinations that might exist within the pizza thread readership and/or eligible voters.