Another thing with Cosplaying is that it's CosPLAYing... half of the fun is the costume, the other half is becoming the character. In Animania 2004 there was this awesome Kaonashi (Spirited Away) Cosplayer who never once broke character! When he was on stage the MC asked him a string of questions (as you do) because the judges want to know how much effort went into making the costume etc., and the whole time all he said was, "uh... uh... uh..." -- it was brilliant! He then later turned to the audience and these gold covered chocolate nuggets shot out of his wrists.

So I think when you dress up as the character you gotta _become_ the character. In Supanova 2005 I won a cosplay prize despite the fact that I was wearing NO costume, because:
1/ I completely became my character, and
2/ The character I chose is an official existing character yet has no physical form!

The character was the Malice of Sauron (Sauron's will that inhabits the Ring and speaks to Frodo). I won a prize for originality. (hey, I got a free DVD from just wearing an Autobot T-shirt and saying "Ash nazg durbatulūk, ash nazg gimbatul, Ash nazg thrakatulūk agh burzum-ishi krimpatul" (it's the Ring poem in Sauron's language).

Getting back to Transformers Cosplay, I forgot to post a pic of my Ratchet cosplay I did back in 2006.