.My comments all use a "noreply" email address, instead of my actual email address. How do I have people email their replies to my comments?These are people who have updated their Blogger accounts, to use a Google or Google+ profile. Neither Google or Google+ profiles provide the option to
Show my email address
It appears that, with the deployment of the new Google / Google+ profiles to Blogger, Google is making yet one more attempt to convince us to network using Google+ - and keep our email addresses to ourselves. If you moderate or monitor comments to your blog, you may have recently noticed many non anonymous comments labeled with a common email address of "firstname.lastname@example.org", instead of personal email addresses.
People who intentionally wish to expose their email addresses in their comments will need to revert their Blogger accounts to the Blogger profile. If this is a concern for you, go to your dashboard. From the menu attached to the gear icon at the top right, select "Revert to Blogger profile", and you'll have your Blogger profile back. Then edit your profile, select "Show my email address" under Privacy, and you'll be back to sharing your email addresses in your comments.
It's likely that the noreply email addresses are being offered to keep many bloggers from, inadvertently, exposing their email addresses to email mining techniques. In remembering the long ago discovered "nice blog" spam, it's possible that "nice blog" spam was originally developed to help the spammers gather email addresses, using very innovative technique.
All that an imaginative spammer has to do is to post a "nice blog" comment, select "Email follow-up comments to me" - then watch as the Inbox fills up with follow up comments from bloggers, willingly giving up their email addresses to every stranger also selecting "Email follow-up comments to me", in that comment thread.
The people willingly providing their email addresses, to the world in general, are perfect targets for hackers later trying to brute force access to the Blogger accounts, using their email addresses.
If you decide to revert to a Blogger Profile for posting comments - or even if you don't - consider using Google 2-Step Verification, to protect your Blogger / Google account from hacking.