A great .NET Rocks! webcast featuring Ken Getz talking about VSTO 3.0.

http://perseus.franklins.net/dotnetrocks_0279_ken_getz.mp3

The VSTO discussion starts at about 15 minutes in.  Some gratuitous quotes:

"These folks have just done an amazing job"

"For VS 2008, they've made incredible strides... I think they'll finally hit critical mass with this fourth version"

“Things that were incredibly hard are now very easy”

“My jaw dropped when I saw how easy it is to create an Outlook form region”

“The ClickOnce thing is really really huge”