Preface: I've run LauncherPro from day one. I started evaluating ADW Launcher today. So I decided to try Kies again. I set it up and hard set my USB connection on the phone to Samsung Kies. I plugged in my phone and didn't even get the notification from Windows that a USB device was plugged in. I unplugged the phone and plugged it back in, this time watching the phone. A very quick message popped up on the phone that said "PC connection available only in idle screen. Close running applications." I checked TasKiller and there wasn't anything running. I scratched my head for a minute and then on a hunch used Home Switcher to change my default and running home screen to TouchWiz. I plugged/unplugged my phone and it worked! It said "MTP application", gave the USB symbol and connected! I then switched my home screen/Launcher to LauncherPro and tried it. It failed like ADW did with the same error! I'm not sure what gives there, but it's something you may want to investigate if you're having trouble using an MTP application like Samsung Kies.