IGN really and even that has things I don't like about it. I never really looked up to other boards....I'd rather follow my own path. Unfortunately my forum luck hasn't reached big board status since like 2008
I used to look up to IGN because of the account system in which you can create a colored username, but then I found a new community and fell in love with vBulletin for how design can be done. I even dreamt of designing a similar site, but was a little too late to create a forum.
I spent the next few years doing trial and error, then I became more savvy with forum software until vB4 screwed up my love for the software, then xenForo is here.
Today, I've been inspired by TheCODForums (used to be COD4Boards) and has been for years. I look up to it for "I want to get there. That's where I want to be."
Considering their size, it never ceases to amaze me how fast Gaia is. I remember reading an article some years ago about how little of the original phpbb code is still intact and how many servers they were using to power their forums.