Steve Jobs commented at the launch that "VoIP will be allowed over Wifi, but not over Edge/3G".
Engadget has the best reporting on the event:-
http://www.engadget.com/2008/03/06/live ... onference/
We'll have to wait a "few months" for the new release, but in the meantime the developer SDK is available here (site down no doubt due to load at time of posting this):-
http://developer.apple.com/iphone/program/
It looks like a nice implementation of a platform. There's no doubt we'll see a mass of applications being developed, in part as a result of a $100m bounty which has been offered by VC firm KPCB to startups looking for investment for their iPhone apps.
Speaking of monetisation, the distribution plan Apple have is via the iTunes store. So developers will submit their applications to the store, can set their own price, and get 70% of the sale revenue (paid monthly) while Apple keep 30%. Apple have indicated that their 30% is to fund running the store, for them this is a non-profit exercise (they still just want to sell hardware).