So here is the status of my .NET 2.0 application conversion. I converted the 71568 lines of C# code and 38452 lines of VB code in the business object and services tier with little error. No errors really, just a few things that Visual Studio 2005 warns about that Visual Studio 2003 did not.
When I got to the web portion, I started finding lots of interesting errors. It's going to take a full day or so to go through them all.
All in all, it's not as scary a proposition as I thought. It's the kind of conversion that can be completed in a couple of days. I thought it might have required weeks before.