Just came across this great online community for people learning or looking to learn guitar. It's run by Jason Shadrick of US-based National Guitar Workshop, and is powered by Ning.
When I signed up to take a look round (I'm always interested in communities of people teaching and learning) the founder friended me immediately (and not as an automatic response either. And he messaged me back too!
So if you're after a friendly online guitar community, go check it out.