Navteq says in the
link that they will update every 6 months. I think dynamically updatable means it can be changed more frequently by driver experience (eg: like Navigon's MyRoutes) but Navteq won't update it that often. This info really shouldn't change much. I think semi-annual updates are sufficient once Navteq get's it's initial data density up to par.
The real question with the Navteq data-acquisition is how many devices send probe data back to Navteq. Nokia only appears to send data from users of Ovi Maps - and very few of the American crippled Nokias permit Ovi maps. We'll have to see if the Magellan 4700 phones home, and if any other upcoming Navteq-enabled devices do as well.
I agree with Gator that even with these limitations in North America, Navteq should catch up to IQroutes in a year, but I suspect Teleatlas to catch up to Navteq in North American road accuracy in a year also.
Tomtom will lose its IQrotues edge, and then we'll all be comparing devices on the next generation of features. LIVE/HD traffic has a huge advantage over competition right now, but I could see competitors closing the gap there also.