The other reason it won't happen is because of the other CMS systems out there that already use MySQL. Just for fun, I did some research on these and focused on Joomla! - it is a very cool system. I like their Administrative interface for managing the web site.
For customers requiring serious web application functionality, I would still favor DNN (primarily because I'm not too proficient with PHP - yet) - but for basic websites that need a CMS, I'm starting to use Joomla! now. The number of free extensions for Joomla boggles the mind - and there are a host of 3rd party commercial modules that rival any any of the DNN modules I've used with respect to the functionality they offer.
Besides, it never hurts to diversify...
Over the weekend I re-built our family website using Joomla! - www.sunsethillranch.com