Google clearly says 300000 "Phones" and the Galaxy Tab cannot make calls. And they have no way to give you numbers that they can't count - so they aren't selectively giving you phone numbers - the other big part of Android is not tied to Google activation system and so there is no way for them to know. (Nook _is_ Android - 2.1 version to be specific - whether or not Apps are allowed to run on default version is not relevant.)
I guess where you are getting at is Android == Google and nothing else and it is somehow OK to compare Phone numbers to 3 separate categories put together because of your assumption that Android=Phones=Google. That's clearly not true but I guess from the down voting that I am disturbing a good number of fans with numbers so don't be worried - pick the number that makes you happy ;)