To date there are only two .NET framework:
.NET 1: including 1.0, 1.1
.NET 2: including 2.0, 3.0, 3.5
So .NET 3 is the next biggest thing to come.
Sadly PDC2007 was cancelled. My guess will be a 08 fall, with Windows client after Vista (anyone dare to leak the code name here? We'll remember you in our heart. )
Maybe more SaaS product as well.