I wish there was a Heroku for Drupal. Over the last three years I've learned how to twist that poor project into all sorts of fun shapes. Deploying it quickly and reliably on a new domain is a real pain in the butt though.
They're awesome folks -- the same people from Chapter Three in SF. They already have some high-paying customers, so I imagine they'll be around for a long time.
Holy cow. Just signed up for the beta and watched the demo video from DrupalCon. This looks terrific. Thanks for the heads up! The list of the tech stack they give you is absolutely perfect.