This doesn’t affect just ASP.NET developers, however the article concentrates on Microsoft technologies.
How to Make Your Web Site Work with Windows XP Service Pack 2 shows what you need to do to be prepared for the changes to Internet Explorer, principally how to design safe pop-ups.
XP SP2 will be pushed to all current XP users, so every web developer should at least give these new guidelines an overview.
Jump Start Git, 2nd Edition
Visual Studio Code: End-to-End Editing and Debugging Tools for Web Developers
Form Design Patterns