I have a June 2012 MBP, and just upgraded to Mountain Lion over the weekend. OS X is generally about incremental refinements, rather than reinventing the wheel every time. All my apps work as they did under Lion. (My first MBP is still running strong on Leopard.)
@ bryonsos: is the latest version of uTorrent for Mac worth a damn? Traditionally, the Mac version has lagged way behind its Windows equivalent. Older iterations of the Mac version are banned on some trackers, including Dime, as they do not relay accurate stats, and are generally very buggy.