I think it is unreasonable to expect people to have an internet connection while driving around town. I do have a phone that provides this through GPRS and bluetooth, but that data transfer costs money for every byte, and having the GPRS active drains the battery. GPRS is fine for quickly checking one's email (and I have been very grateful for having it in the past, while checking my email or looking up something on Google on my Palm). It is not really practical for driving around town.

So, saying that Maemo Mapper requires an internet connection for dynamic routing is, in my opinion, no different than saying it does not have dynamic routing.