BPA member Ascentn was recently mentioned in a new report from Gartner on model-driven compostion of business processes.  The report provides an interesting discussion of three different types of process models; parametric models, configuration models and explicit process models.  Ascentn was the only .Net BPMS vendor specifically called out as supporting explicit process models. 

If you have a subscription to Gartner the article can be found here: http://www.gartner.com/DisplayDocument?ref=g_search&id=736520&subref=browse