I think she/he means a hosted email replacement. At least that's what I'm hoping for.

Fastmail.fm. Even updated their web app recently and it is, in my opinion better than Gmail's.

As a light email user, I wish I could use my own domain without jumping up to the $40/year plan. (Yeah, it's only $3.33/month, but still.)

Hmm, it looks like I could do a "family" plan with one user for $15/year with custom domain.

Yes, and you can actually have multiple domains - one primary one, and set up aliases with any others. They also host Jabber on your own domain with Family and Business accounts.

some domain registrars give you email forwarding.

Do you really think Thunderbird is a replacement for Gmail?

Come on.

Do you really think Gmail is a replacement for Thunderbird?

Come on.