OpenID for Email Verification?

I have a need to verify user email addresses, which I’ve been doing the traditional way - sending an email with a secret to the user’s address and having them reply or click on a URL.

Unfortunately this is not optimal - emails tend to not make it to the user, go into bulk/spam buckets, and are less real-time than I’d like. I’m looking for a better way.

I’m hoping OpenID will help me. I mainly care about Yahoo, Google, and Hotmail, all of which support OpenID to some extent.

I believe OpenID Simple Registration is what I’m looking for. I have a lot of homework to do to see which providers support SREG, how to use them, etc. I’ll post my progress here, and if you have knowledge / experience with this, please leave a comment below.