I think what comes next is the true digital business card - something that easily bridges the digital and physical space to share this great collection of information about who I am.
Without question, one of the best case studies for how social technology can impact the world for good is www.kiva.org. A powerful mission, spectacularly executed.
Like the whole debate around whether or not the Tipping Point is dead (http://tinyurl.com/288roe), could it be that there is space for both marketing and PR to lay claim to their piece of the social media pie?