I have a 50mm 1.8 also, but I stopped using it as much when I got my 55-200mm.
oo!!!!! almost all I can say. 50-200 looks live very very very nice one (I dont have it my small arsenal). but... 50-mm is super great one, for some sort of stuff. I am a fan! but I better go with Sigma 1.4 version, then Canon 1.8 version :P @kaelci