Not that it's the most reliable of sources, but OnStar on Facebook confirmed this morning that the 2011 vehicles have a newer set of hardware that is supposedly required for the mobile app to work.
http://www.facebook.com/#!/posted.ph...14505658599252
I call BS - if I can request OnStar to do all that stuff through voice communication over my mobile phone I see no reason that couldn't have an app to do the same thing.