Craig up on the home page in particular wrote a long article on it lamenting. I've looked over what Google plans for Blink, and the webkit developers are planning to sheer off the Chrome specific code. I think for the end users this is a win/win situation - they will get more compact rendering engines for their respective devices.
As web developers its another rendering engine to test.
The engines should behave much the same for the next year or so. We'll see if blink addresses any lingering webkit issues that the team lets slip.
One thing I do like, while Blink plans to honor the existing -webkit tags, it's other experimental tags will not be prefixed BUT will only work if explicitly enabled from the browser config panel. When they finalize, they'll be turned on by default. Hopefully this will put an end to premature deployment of features in the wild.