>I would be interested in obtaining some feedback from those who migrated from Visual Basic to VB.Net. I heard a lot about the fact that it's a totally different environment and the learning curve was something. Anyone would like to comment on it?

Played with if since the Beta 1 release, late November 2000. It is such a redical departure and such an improvement. Yes, be prepared for spending time learning that new beast.

When I have to come back to VB6, it's now painfull.

Perhaps the single most improved technology is ASP with ASP.Net. Both technologies are light years apart. Simply no comparaisons here. You you have fully compiled code and no pain deployment (no more shutting down IIS to install a new version of a DLL). Microsoft applied the concept of RAD development that you have in VB to ASP.