I am in the camp of people who think that nanotech will not be a "market" but that it will influence all other existing markets instead. Sure, there will be a market for nano-tech tools but even those will be broken out into vertical market toolsets and technologies so textile manufacturers will not be buying the same tools as tire manufacturers (or at least they likely won't).

This is a very good article which articulates a wide range of industries that will be affected by nanotech developments. The message is essentially that it will be everywhere, it will be very disruptive (in the economic sense), and it will be hyped to the point that one will need to invest carefully. Overall, an excellent article.