I've never been a big fan of the O'Reilly series, but I thought this title might be an interesting read. The book takes a look at building portals with a mix of the latest .Net 3.5 offerings including AJAX, Workflow Foundation and LINQ. One thing that seems to missing from the list though is Windows Communication Foundation. The book is fairly light weighing in at around 290 pages including index. By the standards of the other books I've read lately that's pretty light, maybe I can finish it in a couple of days. I'll post additional thoughts once I complete it.