I must admit I do find it disconcerting when I get an email from somewhere with my password in it.
Generally I expect either to:
Not be sent my password at all, but an activation link to confirm my email address.
or:
Don't let me choose my password, but send me a random one - which I am forced to change on first sign in.
Tal's point about Effort/Time vs Reward is a completely valid one, though, and I don't think this is something that should be prioritised.
How easy would it be to add a note underneath the password field on registration saying "password is emailed in plain text after registration".? As a compromise?
