ATL 3.1 will bring major enhancements, especially in the ATL source files editor. Here is a quick overview of the new features:
Open declaration (both available with F3 and Ctrl-click)
And finally, the long-awaited advanced content assist... now working at any level on OCL expressions and enhanced with code templates
At this time you can test those new features using latest ATL CVS (HEAD branch) source code.