There is no platinum edition. Either its the “core” package or the premium package or it isn’t.
The difference between those packets:
Core has a wired controller, premium has a wireless controller.
Core has only a standard TV cable, premium gets a combined HDTV/SDTV cable.
Core has a grey disc drive cover, premium has a chrome tray cover.

The premium gets adittionally a HardDisc drive and a Headset.

However all harddisk attachments have a brushed metal stripe. Even those that you buy in the store to upgrade the core console.

By the way: xenypoo is wrong. *All* Xbox 360 can play DVDs.
And *no* Xbox (not even the premium) is able to burn discs.

I was told that the Platinum edition plays dvd’s, and you can also burn cd’s and dvd’s with it. I am going to get one when I get the money!