Not only do I find it somewhat rude[1], I also think the ability to delete comments is offering a false promise to the user - if you've publicly posted something on a notable site for any length of time, there's a good chance there's a copy of it somewhere else (as has happened with this post).
[1] subject to obvious exceptions like accidentally revealing personal/private information, it being spam/off-topic, or a misunderstanding (editing with a correction is my preference though)
[1] subject to obvious exceptions like accidentally revealing personal/private information, it being spam/off-topic, or a misunderstanding (editing with a correction is my preference though)