Yes and No. There are certainly regional interests, as well as location-specific biases (e.g., there are lots of kindles where people are reading ebooks".
However, I think that the more important point is that in situations in which the vast majority of people used to pull out a laptop (which was often overkill), they are now very often pulling out an ipad. The "pie" is made from whatever crust the analysts want to make it from in order to support their theory/point.
However, as already mentioned in previous posts, the "pie" that matters to developers (showing MY personal bias here) is that iOS is where there's lots to eat!
I would submit that the androids, kindles, and even the surface to some extent -- are the novelty toys that are kinda fun to play with or read a book/watch a youtube, but not to own and cart around all day.
-iamthinking
Agreed. Programmer/App developer know's best. Their income depends on it.