Yes, but the economy is tightening, and people are also used to IM protocols. I imagine people with tight budgets or cheapskates (read: the Dutch ) are interested into this functionality.
Thing is, the 'N900' is aimed at the general public; not 10 Linux geeks. Its the combination of software, the hardware, and the target audience (and probably many more factors) which has potential. Not only 1 of these.