The significant problems we have cannot be solved at the same level of thinking with which we created them. - Einstein
I'm working on a migration of an Application Framework from EntLib 2.0 to Enterprise Library 3.0 (April 2007) for a big client, and I'm quite impressed with Enterprise Library 3.0. This has gotten to the point where it is much more mature, and now sports some very AOP-ish bits with Policy Injection and Validation that really are nicely done -- and extensible.
This is reminiscent of some of the GAT work with dependency injection that Daniel Cazzulino and Victor Aprea were doing a little over a year ago when I talked with them at the 2005 MVP Summit.
There are still a few rough edges, namely that WCSF integration (coming late May to a machine near you) is not complete. However, some developers, such as David Hayden, can't wait, and David has done his own integration (probably cursing all along the way) which you can download.
I can see a growing tide of developers who are ready to embrace these P&P Guidance and Library bits and really start to integrate them into enterprise - level frameworks to build better and more rigorous applications with standardized ways to "do stuff we want to do". If you are building an enterprise-specific application framework, you can base the whole thing on EntLib and standardize across all your developers and teams. Think about it: wouldn't it be nice to have 20 developers all doing their DAL dance the same way, instead of 20 different ways, none of which are as robust or well - thought - out as the single solution?
Recommended. Some study required.