Your statements contradicts the official rules. they say 450x130 is the limit
http://is.gd/f1YJs
I'll be cool with keeping anything and everything within rules, but i'd like to see the rule applies to everyone and that means EVERYONE (in my thread alone there are loads of signs by ppl which are much much bigger than 150x130, btw 150x130 is just square-ish, its an odd kinda resolution that i heard about, from you).
I modified my sig to be under 450x130, once the official rules page is modified to what you claim, i'll reduce the signature size further.