Over the weekend when I was reading my del.icio.us clips, I saw a link to this Business Week article that you can read here. While scanning the article I came upon this quote from Greg Wilfahrt (Our former PR guy at MP3.com until after the Vivendi acquisition):
"Besides, these social networks, typically catering to 18- to 35-year-olds, could make additional money off the ringtones, games, and music downloads this demographic favors. "We could be bigger than Microsoft," contends Greg Wilfahrt, co-founder of SMS.ac. Clearly, that's a bit of an overstatement, even if SMS.ac's sales have been growing 50% a quarter for the past two years."
I am betting that Microsoft isn't too concerned about SMS.ac just yet. :-)