It has been longer in arriving than I would have liked, but the June CTP of the Entity Framework is finally out. This includes a HUGE set of changes. I can't tell you how many times lately I've responded to a question on the forum or something like that with "that's fixed in the next CTP." Finally, it's here. Here's a partial list of the features (largely plagarized from the ADO.Net team blog post on the topic)
I'm sure there's more in there, but that should give you a taste of things. That's all the good news. The bad news is that all these changes brought along with them a number of API and metadata schema changes, so if you have apps you've been working on with beta 1, a number of changes will be needed to get your apps working again with this CTP. If your experience is anything like mine, though, the real major changes in your app will come from taking advantage of all the new features to completely remodel things with associations between subtypes and RI constraints, to use span, etc.
As always, comments and feedback are more than welcome. We're really looking forward to hearing what you think.
P.S. One other small bit of bad news: Complex Types didn't make it into this CTP. So if you are holding out for them, unfortunately you'll have to wait for the next round.