Microsoft is already looking at the tablet market and expanding Windows Phone OS to the tablet market - perhaps with Windows Phone 8.

Pure speculation, but they're not ignoring that sector. The personally designed and shown off version of a possible form factor Windows Phone 7 tablet by that designer (Umang Dokey) was seen and liked by Microsoft.

Don't forget that Microsoft showed off Origami before the iPad. So Microsoft in the tablet market isn't that much of a long shot.

Oh, and since you stated it... I stuck around because of Maemo. Not Nokia.