I am using ASP.NET 3.5 with Visual Studio 2008. I have a few questions surrounding my website and mobile users.
One of Scott Hanselman's podcasts talked about the Mobile Device Browser File for ASP.Net. This is a file that contains feature information about loads of different mobile devices and browsers. For example, you can check if a mobile device connecting to your site has support for cookies, or find out its screen size, etc.
I've never done any mobile development, but this looks as if it could be very useful.
This is on CodePlex here: http://mdbf.codeplex.com/