Drupal is one of the fastest growing ways to grown online. It gives you a tremendous flexibility as well as a massive library of existing modules which can allow your site to do almost anything very quickly. Drupal Commons for example allows you to build a social network online in an afternoon. Ubercart gives you a e-commerce site in a morning. Civic CRM gives you a CRM system in a flash. You can also build Facebook apps, twitter integration and change everything to totally fit your requirements

Also developers from around the world all understand and use the same Drupal system. This means you never have too worry about a specific developer disappearing, as everyone should understand the site that has been developed for you.

With the development of Drupal Commons it really becomes very simple to build a community site, it makes much more sense for people to consider using Drupal than one of the commercial systems which might tie you down and stop you changing or growing the system. It is also much easier to customise it.

If you need any help about building growing a Drupal site drop me a line and I be more than willing to help.