Is this the under the same group of people? the site is different...sorry for the dumb question...new to these stuff
Same people, one domain (org) is for development of the software, while the other (com) is a company dedicated to hosting blogs using the software.
You can download the Wordpress blog script from Wordpress.org; on the other hand, wordpress.com lets you host blogs and gives you a free subdomain for the same. So unless you want an ad-free, no revenue yourblog.wordpress.com type blog, you should go for Wordpress.org. Hope that clears it up - I was confused myself in the beginning but sometimes google helps.