Should I have multiple content management systems together?

I love Wordpress as a blog. It also has some plug-ins that Drupal doesn’t have, as well. In addition, I love Drupal for everything else. Would it be a good decision to have Drupal as the main content manager and Wordpress in let’s say the blog directory, but as it’s own entity?

Not to mention, I do like PHPBB and could have that in the forum directory, or I could designated “” and “” for these things (my host does support that). My question is, has anybody done this and has been successful with it? Is there perhaps a better rule of thumb, or any for that matter? Are there more upsides than downsides?

You’ll need to maintain multiple scripts
You’ll need to skin all the scripts so that they look the same
Your users will need to maintain separate logins and the such for each installation unless you code a bridge of some sort between the three

Everything sounds good, except I’m not sure if they’d like the multiple logins! I don’t think it would make sense for any site to have that, unless they were for different promotions. Perhaps I could write modules that would link the three accounts together.

In this manner, the Drupal account would link to both the Wordpress and phpBB account, as if they were all connected. I’m sure the themes would have to stay with the same consistent look and feel.

I would stick to Drupal out of the three, except I don’t know if they have modules that could mimick the same features as both Wordpress and phpBB. I will ask this in the Drupal forums, as well.

It would probably make more sense to ONLY use Drupal, and then try to find a blog/forum add-ons for Drupal. I’m sure they exist! However, if the blog doesn’t need to be integrated with the site (e.g. sharing users), then you could get away with setting up a simple blog on WordPress and then designing your theme to make it match the Drupal site.

I still think it makes more sense to use only one CMS though.