*sighs* dunno if we're planning on doing that, but it'd be a long time before it would happen, if so. We have loads more work that MUST be done before adding something like that as a feature.
Aside from that, there is the question of protecting the member db at large from spam harvesters, among other things. Which is why email addresses themselves are hidden currently. Plus, we have no way in that piece of software to allow for secure mail, like you can do here in forum. By that I mean that if a user wants send another mail, the forum automatically masks your sending mail information and shows it as coming from the forum. So, as you can see, there is much to just mail funtions in programs like this in general that has to be looked at.