One possible route.
As citizens of the modern first world, we are all duly familiar with the idea of people having multiple fronts through which they can be reached. The home phone number, the mobile number, the Facebook ID and the email address and probably 2-3 chat clients as well. These days the least common way of getting into contact with someone is actually calling their name.
And now Facebook is apparently building a phone. If real, the Facebook phone has the potential to change the way we view communication on a fundamental level. And here's the fun part- this change will actually bring us more in line with the way our ancestors did things.
Back in "the day" there were two ways to reach someone. You either sent a letter (addressed with their name) or you physically found them and started talking. People were their names. Then the telephone got popular and suddenly people were their names...and also this long number. Then the Internet came around and with it, the idea of masking your identity under avatars and screen-names.
Stop what you're doing. Go find a WoW-addict or former WoW-addict in your life (any other suitably compelling online game will work) and call them by their screen-name. Odds are, they'll respond. The same is true of IM and IRC profiles for many people.
One of the central tenets of the (still just rumored) Facebook phone is the merging of a person's contact data into their Facebook ID. Click on a person's profile picture or name and you'll be able to call them. It's reasonable to presume folks will be able to consolidate all of their contact data this simply. Imagine pulling up a Friend's Facebook profile and being able to call, text or IM them at a touch.
It's like Google Voice...but for everything. You could consolidate every one of your IM clients together under one name. Any IM sent to "you" could provoke a notice in all your running clients that a message has been received. You could get an email or a Facebook message informing you to login. Or, Facebook could just go the extra mile and sync everything up. It would certainly be possible to link up all your IM clients seamlessly.
Imagine having every contact across your IM clients merged into one big list, on your phone. Anyone trying to contact you through any medium would just need access to your Facebook account. Communication would be easier than ever...and Facebook profiles would become that much more valuable.
Of course, we don't know yet whether the Facebook phone will ever be more than just a gleaming dream in some nerd's eye. If it is real though, I think it could be a big step forward for the way we communicate on-the-go. Facebook has a chance here to dream bigger than Google. Let's hope they seize it.