Unlike Windows Mobile, Windows Phone 7 is extremely locked down. But similar to what we wrote about earlier, developer Chris Walsh has made major progress on cracking open Windows Phone 7's hard shell. Shown below are two videos showing file system access on his developer-unlocked Windows Phone 7 device:

It's far from a cheesily named click-and-jailbreak program, and it requires that the user be a registered developer. Ironically, if this source gets released, Microsoft may start having more developers than expected. Which is what they hoped for, right?

[Via: WMPoweruser, Chris Walsh]