Eliot van Buskirk reports in his blog:

I just spoke with Tim Westergren, founder of Pandora, and he told me a SoundExchange exec just promised - in front of Congress - that SoundExchange will not enforce the collection of webcaster royalties under the new rates that would have driven many of them out of business.

Good news - in so far as that this is a promise not to enforce collection. The rates are still there as far as I understand. And apparently SoundExchange can change their mind - even after promising things in front of Congress…