Lots of nice touches on the version live on Google Maps, including a secret boss at 0.0000,0.00000 and an 8-bit street-view.
Sounds fantastic, plus:
Every Google App Engine application can use up to 500MB of persistent storage and enough bandwidth and CPU for 5 million monthly page views.
This is more CPU than you could expect to get from a cheap Dreamhost account etc., and presumably more reliable.
Google acknowledges that some people are going to change their own experience of our web applications regardless of what we do. Resistance, as they say, is futile.
With cross-origin support and a HttpRequest module for workers (where XmlHttpRequest isn't available).
It's fantastic -- Gmail for RSS. If Bloglines hadn't just made their only decent upgrade in months, I'd be switching. I still will if the Google people integrate some means of easily re-blogging to del.icio.us &c.
Google's new RSS reader. Excellent if you read entire every feed to which you subscribe; bad if you skim headings, leave some to collect dust for months on end, etc. Great built-in player for podcasts.
Fantastic! No more messing around with faking
In-Reply-To: headers in Thunderbird!
GWA tries (tried? apparently it's been fixed) to cache all links, including those which (e.g.) delete content. As a comment points out, God forbid you have it running while using phpMyAdmin...