The most recent Netbeans podcast had an entire show devoted to Seam. The discussion focusses primarily on the EJB3-JSF integration aspect of Seam, which is a shame because I don't think that part of Seam is really the most compelling feature. There's some interesting discussion of IDE support (it is a netbeans podcast, afterall) and some very insightful comments on standardization and the JCP.
http://blogs.sun.com/roumen/entry/netbeans_podcast_episode_22_seam