Steven Peck, associated with the Drupal project, wrote about an article he came across regarding a comparison of the vBulletin forum and Drupal's forum. The article is titled, Goodbye vBulletin, Part 1: Reasons to Switch. The author of the article writes:

The aim of this article is not to poke holes, or say ‘vBulletin sucks’, but to provide constructive criticism of a successful product, proving that vBulletin is not always the best choice. In places the article compares vBulletin to Drupal, this is the platform The Webmaster Forums will be switching to and represents many of the things vBulletin should—in our humble opinion—aspire to.

Mr. Peck's reaction to the article (and my emphasis in bold):

Now this was a interesting. A well written article on why one site is switching over to use Drupal's built in forum rather then continue to use vbulletin.

In other words, Peck and many of us that pay attention to how the forum applications stack up against CMS native forums don't see too many articles like this. It is rare to see someone using a standard forum application such as vBulletin, SMF, or phpBB switch over to Drupal primarily for its forum functionality.

I think the tide is turning though. Personally, the biggest difficulty I have with using forum-only applications is the difficulty of fully integrating the forum with other Web applications. While a site owner may start out wanting to host only a forum, sooner or later there comes a time when there is need to add more CMS functions than a forum-only application typically provides.

I maintain a site that started out only as a SMF forum but later needed eCommerce functionality (we chose osCommerce) and it now needs blogging functionality. If a site is the sum of all its parts then the site I'm maintaining with all of its non-integrated applications isn't adding up correctly.

While there are work-arounds, third-party bridges, and patches that can be applied to these applications...these mashed sites still rarely achieves "oneness" with all the required applications. And if you are lucky to end up with a fully integrated site via a lot of hacking the core, it only takes for one of those applications to require an upgrade to cause a lot of additional cost in time and money to re-integrate the changes back into your hacked site.

I know a lot of forum-only people that would not be happy with the forum module in Drupal as it is today, however I think we're all headed in the direction Drupal has taken. No, I'm not saying we're all heading to Drupal. What I am saying is the wind is blowing in a new direction where people are wanting more than a forum or a blog or a shopping cart for their site. They're realizing that they need to start using well-rounded CMS applications that provides more than one or two CMS functionalities.

Yet, so many of us are trapped because we chose the easy route of using only a blog or forum application when we started a site. We now find that we need so much more for our site but have no true migration path to a full CMS. I know this to be true because I've been there, done that, and for some of the sites I maintain still do that. The trick though is making sure you and I don't repeat the same mistakes when starting new on the next new project.