The newest Xcode actually doesn't ship with gcc, which is the complaint here I suppose. It hasn't impacted me all that much, but I don't use a ton of non-OSX specific software (and none outside of homebrew/ports).
but gcc-4.2 is the real deal gcc-4.2 --version i686-apple-darwin11-gcc-4.2.1 (GCC) 4.2.1 (Apple Inc. build 5666) (dot 3) Copyright (C) 2007 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.