I finally figured out a way to fix the Blogger comment issue, and have told a few people, but it's going to be quicker just to post about it.
Go into 'Settings' at Blogger, then to 'email' - reset the 'comment notification email' address to another of your email addresses, then save. You'll receive a confirmation email at that address - just click and you're golden.
I'd originally had a non-gmail address as my notification addy. (You know, the email address that I've been using for the last 20 years and see no reason to give up now...) I changed to one of my gmail addresses and it's now working perfectly. I don't know if it's just because of the gmail addy, or just the fact that I changed and confirmed that makes it work now, but I'm sure glad to be getting comments again!
Spread the word!