For a long time the application architecture guidance from the patterns & practices team remained unchanged... and it was inherently necessary to give it an update with all the new technologies and also trends appeared on the market.
Now the first messages are out... just take a look at the blog of my peer Cesar from Spain - he created a pretty cool mind-map with the topics addressed by the new App Arch Guidance.
Check out the following links:
Cesar's blog entry on App Arch v2 J.D. Meier's blog entry summaring new guides Application Architecture Guide v2.0 Info Key Features of App Architecture Guide v2.0 The Meta-frame for the App Architecture Guide
I hope that the team will release the guide as a printed book as well as they did with the previous version of the guide. I'll definitely spend one of my upcoming weekends reading the guide;)