They have a video which shows a "proxy connect".
http://screenr.com/rnn Part 1
http://screenr.com/hHl Part 2
Is this something Xenforo is planning on having? The Wordpress market is HUGE and a lot of people are looking for an easy to use solution built in.
Vanilla is a bit clunky so would prefer to use Xenforo. I saw some of the mods on this site but they seem complicated to set up and use and will they be supported and updated in the future? Who knows. Something built in the core Xenforo would be best.