From Netflix Q4 2011 Letter to Investors:
Domestically, we grew faster than expected in streaming members (up 220k to 21.67 million) in Q4. October and November member trends were consistent with our expectations from our last earnings call, while in December, we not only returned to strongly positive net streaming additions (aided by strong seasonal gross adds) but exceeded our forecast. In particular, we saw fewer streaming cancellations, as well as lower migration to DVD-only plans, resulting in the outperformance for streaming members.
The domestic streaming segment delivered $52 million of contribution profit, or 10.9% contribution margin. We exceeded our domestic streaming contribution margin target of around 8% due to higher than expected streaming members and revenue, as well as some under-spending in both content and marketing
Fun fact: Netflix now has almost the same number of subscribers as Comcast (21.67 million versus 22.4 million for Comcast).