Some thoughts.
I think the Nokia N900 has enormous potential. Even without carrier subsidy, its possible the prices of the phone may fall to the 500 or 600 level. If this was isolated on a national market like say, the US or UK only, that would be disaster. But with Nokia's global distribution, it can still find enough adopters even at that price to sell a few million. Once that happens, its possible to start an ecosystem, especially if the users are wealthy, at least so to buy the phone, which means they got data plans, disposable income to buy apps, and the education or technical level enough to realize the phone to its fullest potential.