goodroi - 6:11 pm on Mar 13, 2012 (gmt 0)
Vanessa posted a useful review of this issue (including explanations and a list of what's missing) at Search Engine Land [searchengineland.com...]
Besides all of the useful info she covers, I noticed she also said:
I have questions into Google asking about the removed functionality (particularly the confusing changes such as the Not Followed errors) and Iíll update this story as I hear back.
That should make for a useful follow-up post.