The only problem is when somebody wants to use Ctrl+V to paste AND wants /lines to be interpreted as commands, but realistically, I think it's a non-issue.
You'd be surprised - on QuakeNet, lots of people use ctrl+v to paste the auth command from the email from Q, only to find that because they copied the trailing newline from the mail as well, their username and password end up on the current window (which is sadly often a channel).
That said, I miss the ability to paste commands as literal text as well..
