The exact same volume for the last two BTCUSDs?
Here's a summary of the settled contracts:
Dec 15, 2012: BTCUSD-12.12 (BUZ2) Total volume: $500,000, Final settlement: $13.4870
Mar 15, 2013: BTCUSD-3.13 (BUH3) Total volume: $754,550, Final settlement: $47.0764
Apr 14, 2013: BTC/USD-4.13 (BUJ3) Total volume: $754,550, Final settlement: $98.94082
Feb 15, 2013: GOLD-02.13 (GDG3) Total volume: 268 contracts, Final settlement: 65.0314 BTC ($1634.30 USD)
Apr 14, 2013: GOLD-04.13 (GDJ3) Total volume: 119 contracts, Final settlement: 15.23 BTC ($1507.0 USD)
Feb 15, 2013: OIL-02.13 (CLG3) Total volume: 1513 contracts, Final settlement: 3.8709 BTC ($97.28 USD).
Apr 14, 2013: OIL-04.13 (CLJ3) Total volume: 187 contracts, Final settlement: 0.9169 BTC ($90.72)
BUZ2 volume obtained from news release: https://plus.google.com/u/0/117990284188664727142/posts