Level3's blog may be tipping us off to more than Microsoft may have liked. In their year end post about voice predictions for 2012 there is a casual reference to the mobile client of their UC product, Lync, but the "tell" is based upon a "one number" solution.
So let's speculate. When you think about it, Microsoft and Level3 have had a longstanding relationship, dating back to voice running over the Level3 network for XBox for years, and recent efforts around SIP trunking. Now we see a "leak" and a series of references in items 5, 8 and 10, when all taken together and given the relationship history with Level3 start to show some potential directions that both companies are taking.
Level3 for years has been flirting with how to be mobile player. Now that Skype is part of Microsoft and that Lync is the business UC client, the only missing piece is mobile.
Where does the mobile piece come from? Well, if Light Squared gets approved it could be them, or you could see Microsoft and Level3 buy up Leap Wireless or Metro PCS and turn it into a business focused UC player end to end....with Level3 in the middle of it all.