Not having addClassCleanup means that my setUpClass method will have four try/excepts in it, as will my tearDownClass (I have four fixtures I'm setting up for the tests).

So, no, it isn't strictly needed, but it is prettier :).  As Robert says, though, it makes for a nice symmetry in the API.  Basically, I like to see tearDown deprecated, as I find the setup/addcleanup pattern much easier to write and, more importantly, to read.