So I moved it all to the trash and decided to install fresh from the app store. I go to the app store and get to the Xcode page, where I see the "Free" button. I click that and it turns to "Install ...

Made the "jump" from 10.4.11 to 10.7.3 last night. First order of business was getting the Developer Tools on, so I could re-compile the CLI tools. Turns out Xcode 4.3 was just released a few days ago ...