I think it is a great feature actually. It is a way to gauge performance on kw's you never would have thought to try out.
While expanded broad match sounds good in theory, I've found the ROI to be terrible. If your keyword is running shoes and the user's query is slippers, then the relevancy is low, the quality score is low, the ad rank is low, the conversion rate is low, and the only thing high is the CPC. That's why I rarely use broad match keywords in my campaigns. "Automatic Matching" will make it even worse.
There are better ways to come up with new keywords and test them than to let Google do it for you with expanded broad match or ultra broad match.
This feature, if true, is totally opposite to “more control”.
And it's completely opposite to what AWA and other Google reps have long advocated -- tightly focused ad groups.