97%+ of people don't care about passwords being sent in plain text over email for non-banking sites. Or for accounts that have no info until you populate them.
The other 3% can just log in and CHANGE the password after-the-fact.
I'd rather not inconvenience the majority of my signups, nor force my ideas on how things should work on them.
You're living in the past if you think this is an acceptable practice. I don't care how trivial your web service is, if you're throwing my password around willy-nilly, I don't want you.
I like the practice of emailing a link to a page where the user can set their password for the first time.
But if it's a randomly-generated new nonce, seems OK as a pragmatic middle-ground. Folks like us, who care, will log in and change it.
When a user is sent a password via email, unless that user is required to change eir password upon entering it, it is inherently less secure than sending a link.