If you're on Joomla using the Mosets Tree plugin and want to move to WordPress, you can now convert your listings into Business Directory Plugin using the converter provided by Frederic Gilles: http://www.fredericgilles.net/fg-joomla-to-wordpress/mosetstree/
We've worked with Frederic to make sure we are 100% compatible to transfer listing data including Maps and Ratings data (you need to purchase those add ins for BD if you want to use that data in WordPress)
Any issues with the conversion from Joomla, please contact Frederic: http://www.fredericgilles.net/contact/