An interesting discussion on ten leading open source innovators, and the challenges that each of them faces:
Ten Leading Open Source Innovators - http://itmanagement.earthweb.com/article.php/31771_3660831_1
I'm glad to see SugarCRM make the list. I have worked with that application quite a lot and believe it to be one of the slickest web applications around, open source or otherwise, while the team behind it seem to have a very clear focus on what they want to achieve with the product.
Updated 2021 : note that the above post is out of date as it was originally published in 2007, but is left here for archival purposes. I have unlinked the external link as it is now dead.