I’ve been using VS 2005 Beta 1 on a project, and the build seems to be a bit slow on starting, but there is a new context menu item called “Make”.  As far as I can tell, it builds the project just the same, and it does it WAY faster than “Build” or “Rebuild”, so that’s what I’ve been using to avoid waiting for the delay.  The bugs are currently being worked out of the build process, so I’m sure it’ll get faster.