I have an email sent by Rules. Here is the text of the email in the Rules action:
Welcome to x! As a professional user, you can now showcase your business on x by creating a Professional Profile and uploading photos of your best x.
Here is what the user gets (note line breaks):
Welcome to x! As a professional user, you can now showcase your business on x by creating a Professional Profile and uploading photos of your best x.
I'm not sure why there are arbitrary line breaks being inserted in the text when sent via email. I've excluded the RTE on email field in the rule, and included only plain text.
\r\n
somewhere in it. Try retyping the text (no copy and paste). – kylex Feb 6 '12 at 20:00