I'm not sure if the next eight episodes will be considered in Season 5 or not. It doesn't matter because I'll watch them for sure. This show is awesome, but these past eight episodes have been fantastic. You've got the same themes as before, but now you add in Walt's transformation from bumbling high school chemistry teacher to meth kingpin.
Skyler is still my least favorite character followed by Walt, Jr.
All in all, Breaking Bad is one of the best shows on TV so check it out if you haven't already.