I don't have any first- or even second-hand information about these branding rumors. I've asked Microsoft but am not expecting any kind of comment.
I will note that Microsoft has spent a lot to land the Surface brand ever since officials decided to use it to refer to Microsoft's mobile tablet family, rather than its large-screen tabletop devices. The company is continuing to advertise the new Surface Pro 3 massively on TV during the World Cup 2014.
However, the Nokia and Lumia brands have stronger recognition outside the U.S. than they do here. And Microsoft is doing better selling Windows Phones outside the U.S. than here in the States.
Would Microsoft stand to gain more from changing branding at this point in Surface's life -- such as being able to better distance itself from its early Surface history, as well as perceptions by some that the Surface devices aren't selling as well as Microsoft expected -- than it would lose by changing naming conventions at this point? Maybe...
What do you think, readers? Should or shouldn't they rebrand Surface to Lumia -- if, indeed, that's actually under consideration inside the company?