Kudos to Butcher, who pointed out a new Gamespot preview, the second of many in the next few days, I'm sure. The screenshot is the same as the IGN preview, but the content is very interesting. Here's one line that is certain to stir up speculation:

Also, the ring encircling the planet was constructed by a third and as yet unseen alien race, but Bungie wouldn't comment on whether we'd be able to see or fight against that race when the game is complete.

Definitely worth reading... enough info for yet another FAQ update.