I'd like to add that having the application forms, code behind, scripts and resources compiled into a single assembly is also of great benefit (to me at least) as I can a) protect my application from casual prying eyes and b) our infrastructure folks can't break an application by removing a page or javascript or whatnot because they don't know what all the 'bits' of a traditional ASP.NET application are for.  The site I'm working on has just the VWG assemblies, four application assemblies (each is a different application) and a web.config.  A monkey couldn't screw up installing it.   

And since the WVG development model is so much faster than rolling your own ASP.NET (forget about how long it takes to put a fully functional AJAX site together) I had time to add tools like an event viewer, application calling tree and timing trace, security authentication and authorization audit and an aboutbox that tells me who, what, where and when.  Those tools had been on my to-do list for about six month and I finished all of them in a single afternoon.

I haven't been this impressed with any technology since I first saw VB back in the day.  Cudos to all the guys 'n' gals who's sweated blood into VWG.  Outstanding job.