Can anyone tell me the difference (if there is one) between using the replyTo attribute in the <cfmail> tag versus using <cfmailparam name="reply-to" value="firstname.lastname@example.org" />? Thanks!
I suspect there aren't any differences: I imagine the replyto was added to <cfmail> for expediency, given it'll be a reasonably common param to wish to set.
The quickest way to check fro yourself is to send two emails:
Inspect the source of the email messages when they arrive and observe there's no difference.