We have been using mercury/pantheon to host sites for a while now, we love the fact that you can get a fully configured Drupal hosting environment with all the trimmings for very little work. Specifically we have been using linode for our actual hosting, they are well priced, offer a good product and (this WAS the deal breaker) have mercury/pantheon "stackscripts" ready to roll (a linode stack script is essentially a build script you can use to setup your fresh server).
What we hadn't realised until recently is that mercury/pantheon has gotten a whole lot easier to setup - instead...