Okay, here's the "workaround" I mentioned... Works great for me (did it twice, just to be sure)... I cant explain the why or the how, but the device ID somehow changed and was no longer in the driver .INF file, so the phone in debug mode was no longer being recognized... which is why trying to re-install the drivers didnt work.
So, I found the device id, added them to the driver .inf file, and now it will work. It will complain that it is not "signed", but it will work. Im sitting in the adb shell as root right now, again. This appears to be some sort of oddity between Windows 7 and the AndroidSDK usb_driver install. Again, I won't claim to understand the how or the why, but all I know is it works.
Drop the attached "android_winusb.inf" file into the usb_driver folder for wherever you installed the Android SDK. If you used the default location, it would be C:\AndroidSDK\usb_driver\android_winusb.inf ... Then in Device Manager, go and reinstall the drive, pick that usb_driver location, and it should find it. Like I said, it'll complain that its not a signed driver now, but if you say install anyway it will work. Its using the same exact driver dll's as before... the change to the .inf file just tells Win7 its okay to do so.
Hope this helps... I'm terrible at instructions, so I hope this was clear. Best of luck!
EDIT: I had to zip the file, the forum wouldnt let me upload a .inf file. So unzip this, and then drop the .inf file in the directory I mentioned. (
Usual forum disclaimer: It worked for me, but use at your own risk.)