This release adds a number of enhancements, such as "always on" instances (i.e. no start-up time if your app goes idle for a while) and an increased limit for background tasks (from 30 seconds to a whopping 10 minutes).
This addresses some of the recent criticism. GAE looks more and more like a good platform to build your startup product and not have to worry about scaling. It's far more cost-effective than EC2 or Heroku (see some prices in the HN discussion - about $9 a month seems to be common), but does require a lot more contortions to build apps for it. One to watch, for sure.