Apple has shown off an updated version of its MagSafe power port, dubbed MagSafe 2. The new port was shown off on the side of the new, next-generation 15.4-inch MacBook Pro. Apple said that it was "thinner," and upon close inspection of the picture we can see that the edges appear to be curved off compared to the last-generation port. The power contacts themselves appear to be the same — there are still five of them — so we'd hope that there's some sort of backwards compatibility. It's not yet clear if the new port is only for the just-announced, next-generation MacBook Pro or not, but it seems likely that Apple would bring the thinner port to the MacBook Air line, at least, as both machines put a premium on width.
Update: Now that the Apple Store is back online, we have a few more details on the new MagSafe 2 power port. There are both 45W and 85W versions of the power adapter, for the new MacBook Air and MacBook Pro with Retina Display, respectively. Unfortunately, Apple hasn't maintained any backwards compatibility — you'll have to buy a $9.99 adapter to power your new laptop with one of your old chargers. Also, oddly enough, Apple has moved away form the "barrel" style connector and back to the T connection of old. Many users had issues with fraying wires on those old power cords, so we find it curious that Apple has decided to bring it back.