I'd suspect Apple is purposefully trying to disassociate the iPad with the iPhone and realigning it with the Mac line by changing naming conventions. If that's the case, this post is pretty good evidence that it hasn't really worked out so far.
Generally speaking, I referred to my iPad 2 as an "iPad", and when not in the process of purchasing accessories or arranging repairs, I commonly call my "MacBook Pro (17-inch, Early 2011)" a "MacBook", "Mac", or, most frequently, "computer", in line with the common practice of most everybody I know, technically-inclined or otherwise, unless there's some need to either disambiguate or brag.
Except, you know, the Macintosh II...
Or the Mac LC (followed by the Mac LC II and then the Mac LC III)...
Or the original Power Macintosh models (like the 6100, followed by the 6200, 6300, 6400)...
And then the PowerMac G3 (followed by the G4 and the G5)...
Apple has changed from numbered to unnumbered model names (and back) before.