SQL Native Client and Vista
After upgrading to Vista, I tested a form in one of the apps I was working on. What used to be a snappy split second load of the form now took about 3 seconds.
I tried loading other forms that used the same SQL Server connection, which was an SQL Server 2005 Developer Edition instance on my dev machine and got the same slow load time. I changed the connection to a production server with an SQL Server 2000 Standard Edition and got a quicker load.
I tried to create a File DSN with the same local connection and got the same connection load time. I change the driver form SQL Server to SQL Native Client and viola! a much snappier load. I'm not sure why I didn't have this behavior back in XP, though I'm sure this is just the first of one of those quirks during development after switching to a new OS.

