[japanesejay]

It all depends on what you're building but Drupal is an awesome CMS framework that you can extend and mold it into whatever you need. We run a small consulting shop and we leverage Drupal for a lot of our projects. From internationalized corp sites, ecommerce sites (we have a groupon-esqu clone), web apps, and even just as a back-end data store that our mobile apps interface to.

Unless you're trying to really do something super high performance, or have a real good reason why it absolutely needs to be in rails, as we always hear with startup advice, JFDI!

FYI, I know Drupal 7 was just released and its real pretty and shiny but make sure you look into all the compatible contributed modules. Many of them havent been ported over or fully tested for D7.