I am new here, so sorry if this has been covered...

But is anyone trying, or have they been able to edit/hack the default.xex yet? To possibly expand the list of backwards compatible games and/or allow homebrew?

They are trying, but it's very difficult because they're signed and if you change something they aren't signed any more so not accepted by the xbox.

Hey I have found a way to get fresh XEX's and i need to know if real XEX files are needed for the development of exploit software, if you have a modded xbox, back order an Official Xbox Magazine issue that has a disc that can be read by both xbox and xbox 360. these older disc came out just as the 360 had been released and and since been discontinued. i was messing around one day with my modded 'box and thought about those discs. and guess what, the disc CAN be read by a modded xbox and you can see and copy ALL its data including the xbox 360 demos and and other XEX goodies. now, can you tell me if this little trick is worth anything? and if it is where else can i go to get the word out, obviously if its only worth telling if its worth while, it is?

You can do the same with the Burger King games from about a year ago... There isn't really anything you can do other than rip it easier, if you change the xex or any of the files, the signature will get broken, and the Retail 360 will not run the gae