mrojas
Sometimes I do a favour for some companies and send bug reports etc. Not in this particular case of N900.
Next thing - please read what I write before.

My work is different. And I dont care about products, companies much. Due to one reason - I write about all devices/companies. For you may be N900 is a single device, for me one among others. Good to check, but not the ultimate one

N900 are producing now. It means that SW is installed on device now. Not tomorrow, not in October or November. Now. And it wont be updated in a shop. May be it will be updated before going to shelfs. May be. But changes wont be dramatic.

ragnar
Moblin issue is a power consumption, they heavily trying to build small devices but without real success. I see the market for such devices (limited market) by 2011. Not earlier. Depends from hardware.

Bratag
Android is not very strong by now, it is a part of Google strategy. But Samsung wont be a very active 2010-2011 in this field. So it will be SE (most high tier products based on Android X -line - 3 are coming)
Motorola heavily trying to return. And some chineese/taiwaneese companies. Of course HTC. But they all toghether arent strong

Popularity of Android is the question of popularity of next big services from Google which will be shown to public in beginning of 2011 or later


Laughing Man
We discussed this topic in preview of N900 - i called this vertical market - Maemo is the part of such market for Nokia. It will be 3d party devices like MID, later some other devices (may be PND for instance), later even sub-notebooks etc. All kind of devices from different companies.

The same story for others. Apple will have different devices in house. Some others not.