THe vBulletin developers are talking about it here http://www.vbulletin.org/forum/showthread.php?t=174375 - seems its only in beta at the moment.
I only started messing with email and the internet on a mobile this week.
Don't have a bigger screened smart phone, just a nokia navigator.
I can read somersoft emails ok but all the additional text is a pain.
Have given up on browsing the web or the forum. All too hard, and small.
Would be interesting to know how many access posts via a phone.
Forums must waste a lot of bandwidth ... ie have to get the whole page again when a new reply is added - i have always thought a Forum board with a NNTP (newsreader) option would solve this problem. It is being requested in VBullieton forum here ... http://www.vbulletin.com/forum/showthread.php?333896-NNTP-feature&highlight=nntp