The business world is certainly starting to notice Drupal, as evidenced by this article in Businessweek naming Dries as a top 30-and-under innovator for 2008.

Make sure you have a solid business plan and you've done your homework and are passionate about what you are doing, and people will recognize your potential.
--Dries Buytaert, in Businessweek

Businessweek talks about Drupal and Acquia, and mentions many of the great sites that have been built in Drupal. They cite the number of businesses using Drupal at being around 250,000.

Also among the top innovators are Garrett Camp of StumbleUpon, Joe Green of Causes, Drew Houston of Dropbox, David Ulevitch of OpenDNS, and others.

Congratulations are in order to Dries and to all of you, the people who are working so hard to make Drupal a great product.