I just saw that John Papa's excellent book ( Data-Driven Services with Silverlight 2) is now available for an impressive 40% off. If you are doing Silverlight, I recommend you get this book. I tech-reviewed the book for John and think he's got a winner on his hands. It covers how to do server communication of all sorts with Silverlight. The Promo Code DD224 for 40% off the cover price. Offer expires 2/19/09. It is good for the print or the e-book version of the book.
