I really would have hoped that Google would try to live without asking people to link domains to Google accounts. At least that's what I understand they are doing here. If so, this is a step towards their interest, not ours, and their slogan "don't be evil" pales more every day. Yes, of course some newer competitors of theirs are leading this course by attempting to win over people to their own closed messaging worlds, and users at large don't care, so all of this is sad. (The language on their blog post about this (linked from the mentioned post) is laden with a disappointing amount of weasel words, too.)
So what I'm saying is, no, I don't want to link my domains to my Google account just so that I can send mails to them. And I'm going to hold out hoping that their systems are collecting enough trust in my domains and/or IP addresses in other ways so that it won't be necessary.