It looks like April 20th is shaping up to be a big big day for T-Mobile fans as Radio Shack has just outed the Sidekick 4G for launch on April 20th. Perhaps this was accidental as T-Mobile has yet to give any official word. Since we love launch dates and we trust that Radio Shack isn’t yanking our chain we’ll take it and run with it anyway. As it stands, this would be the third device we suspect that could be launched April 20th with the T-Mobile G2X and T-Mobile G-Slate also rumored to drop that day. There you have it, April 20th will be a big big day in T-Mobile land.