My friend Matt Asay has moved to Alfresco (formerly Activiti). Good luck Matt!
I think it's a great move. Since the beginning of 2003 I've been repeating the theme that now is the time for Open Source to go after Enterprise Applications. Alfresco is a perfect example of that trend. Along with other Open Source applications like Medsphere, SugarCRM, Compiere, and Asterisk it demonstrates the vulnerability of Enterprise appplication software and the traditional Enterprise Software business model. The traditional Enterprise software business model is dying. Long sales cycles, expensive pilots, and a high prioced field salesforce are things of the past. Customers are tired of having companies charge them to buy their software. They want to test and evaluate on their own. Open Source gives them that option.