Agree that this was a great series: well written, well cast and with characters I found I really cared about; quite moving at times. Don't think series 3 has been shown in Oz/NZ yet, but I think the reference to 'failure by the BBC' refers to occasions when they've not continued to show programmes, usually to do with cost. They did this with Mad Men - I'd watched every episode and then they just dropped it without warning.
The BBC are not the only culprits. For example, ITV dropped Dexter, and Channel 4 did not show the final series of Six Feet Under - and I'd watched every episode of that, too!