Just curious, but are there any cell phones that have modular radios?
As for getting it, I bought mine off of Amazon. It wasn't that hard.
Nokia was in a pickle long before the N900, nor was the N900 supposed to get them out of it. For example, letting Symbian get old and decrepid and having no strong plan to find a replacement.
People may hate that they tried to retrofit Maemo as a phone OS and the deal to combine with Moblin, but the silver lining is that it might be a better fate for the OS overall. Fact is, I don't know if I see the tablet efforts being more than just a sideline for Nokia. A pet project to see what they could do in that area, with little to show for it corporate-wise. Personally, I wasn't interested until they did release it in phone form.