OK UK listerners, here's what's up with this. The current release of Series 1 is the same as the initial release of the Season 1 boxset in the States, but they've long since got the replacement deluxe version, which includes the 3 hour mini series that kicked off this relaunch (over here we have to pay another twenty quid just for that), and the commentaries and many other extras. So, don't buy this until the complete version comes out.
P.S. This series rocks, so do buy it when the deluxe set does eventually come out