Skype's Skype for Android app is being blocked from being used over most US 3G networks, except Verizon's forcing American Android to use it via Wi-Fi.
However a hacker named Matt, AKA "xeudoxus" has posted a modified version of the app on Droid Forums. Matt has promised more hacks to unlock other restricted Android apps including Blackboard Mobile Learn, which was locked to Sprint, and SprintTV also locked to Sprint.
The Skype for Android hack is a sideload program which means users don't have to get into the root of their phone. Using the Android Central Sideload Wonder Machine you do not void the phone's warranty installing the hack.
The Sideloader is a Windows application that lets you load apps into your phone from your PC via a USB cable. It can be used with any Android device, on any carrier, without the Android SDK installed.
Still it means that Skype can finally work on Android phones in the US, although this will certainly miff a lot of the telcos.