Well you have heard a lot about it and yes, it as as good as you thought it would be.

The map editor is just as Bungie promised. You can save as many games as your 360 can hold. You'll also be able to upload clips (you set the in and out points of a match) or an entire firefight to Microsoft's servers for others to enjoy. That's nice, sure, but it's the functionality that had us drooling. At any time during normal playback, you can pause the video. It's easy to hop to other players and watch from their perspective. Or you can move the camera freely, spinning in any direction, focusing on any point.

All the controls you could want are available. Rewind, slow mo, and even "chapter skip" to move ahead to a later part of the clip. Find a hot visual and you can take a screenshot. Every screen is saved to your 360 and uploaded to Bungie.net, where you can then download it to your PC.