Heh - I had created #bitcoin-btcmine and had been idling in there...
One question - for last block solved, (118405) I submitted 18104 shares against the 166,119 shares total or 10.899%. My bounty was just 4.184 BTC.
I would have suspected 50 * .98 (2% commission) = 49 * 10.899% = 5.34 BTC. Why such a large discrepancy?
Score based payout I think.
Probably before poll solve block some miners in the top submit a little more shares with increased round score (i.e. littleshop or some miners why do not want be in top

When pool get more hash power, I definitely decrease round score magic number, and score will be rise frequently.
This should be averaged anyway in the long term.