Yes and no... it's not really unreasonable to speculate that Nokia, having released a brand new operating system, would continue to build devices that use it. Such a string of devices would drive further development and maintenance of the OS and hence keep it alive and fresh with new features and fixes. Nokia instead have just dropped it in favour of MeeGo which will presumably have a string of devices... who knows, they might just drop that one dead too!

I bought my N900 speculating on this, not that MeeGo would be made available. I think that MeeGo should be made available now that they've dropped Maemo in such an insanely short space of time - but that isn't what I originally hoped for when I got it - it hadn't even been announced when I did. This is an expensive and capable piece of hardware with much room to expand and grow - it's not unreasonable to expect it to do so and I wouldn't call that speculation, just reasonable expectation based on cost and size of manufacturer, compared to other computing goods and hardware's track records (in similar and different areas).