The real world is a very dynamic place where all plans are subject to change. These multi-year roadmaps are never going to be as fixed as some people might like to assume, and a good planner will always leave room to make radical changes as needed. It's only fiction that has rigid multiyear plans which actually work.

For example no one was expecting the Nokia 5800 to do as well as it did, I think Nokia's official prediction was 1 million units for the first quarter but it actually sold over 3 million. That probably had consequences for their Symbian planning and it's interesting that a year later we see four similar devices all on the way (5530, 5230, 5800 navigation, X6).

I would suspect the N97 will sell worse than expected because it's going to be wiped out by the N900 (almost same price but much better hardware) and the 5800 (almost same hardware but half the price) so that too would affect Nokia's plans.

I'm sure the sales of the N900 will have similar level of influence over Maemo's future, whether they're good or bad.