Only if the send you your old password. If they reset your password, they can send you the plaintext first, then hash the password and store it in the database.
a) Work once. If you click on a password reset link and it says it's already been used, you know something is up, v.s. someone using the plaintext password to log in before you and you are non the wiser.
b) Expire. Lot's of people won't bother changing the password that was given to them, so anyone who comes across a plaintext password in the email at a later date would be able to log in.
In that sense, a password reset link is equivalent to a temporary plaintext password.
Except it's got better usability, being a link that you can click on.
http://superuser.com/questions/260002/why-are-email-transfer...
That still doesn't mean you should count on emails being encrypted between servers.