Most celebrities don't use Windows Phones, even if they are seen with one, unfortunately. Like Oprah saying the Surface is one of her favorite things, while tweeting it from her iPad. Or Alicia Keys posting from her iPhone while she worked at BlackBerry. Just because they say one thing, or are seen with a Windows Phone/Windows device, doesn't mean they will use it more than they are getting paid for.
Unfortunately
I see the QB from the Seattle Seahawks tweeted about Microsoft helping him set up his Surface tablets. I wonder if he will actually use them, or if he'll be tweeting from an iPad soon.
EDIT: Also forgot to mention that Microsoft has a deal with The CW TV network to showcase Windows 8 and Windows Phone in the TV show, Arrow. I see lots of Win 8, Surface, Lenovo, Nokia, etc. products EVERYWHERE in that show. So cool.