Realize this is an old thread but hoping for an answer to a new question:

Is it possible to integrate Joomla into WP instead of vice versa? I'm trying to setup a paid directory website and, being a WP user (gave up Joomla in its Mambo days and haven't returned since), naturally searched WP plugins that would execute desired functions (i.e. advertiser can automatically fill out online form, upload company contact info, images, list in categories, and submit payment, etc.). Was only able to find WP Directory Pro that came closest to fulfilling my needs. Out of curiosity, frustration/irritation, and hope that there was something more complete out-of-the-box (I'm not a coder or developer so every little bit helps), I checked what Joomla had going on and found SOBI2 which is gets me A LOT closer to my goal without having to really mess with code.

However, I still like the look and backend usability with WP. Since I would use SOBI2 for only a portion of my website (a page called "Directory"), would it be possible to install Joomla into a subdirectory or subfolder (I know, shoot me, I warned that I'm not a developer) of WP which is already installed into the root of the website? Essentially, I'd be using Joomla just for the SOBI2 extension and would like everything else on the site to be WP. I realize I'm probably not making much sense since I'm mixing up the terms but hopefully someone knows what I mean and can point me in the right direction. THANKS!

Great site, by the way! Just found it today and I'll be keeping up with it.