I'll be putting up a poll this week on the BTC Guild website to see what the users want:
A) Payout Change
1) Proportional
2) SMPPS
3) PPLNS
4) Straight PPS [will require a much larger fee due to risk]
I say use the KISS method (Keep It Simple Stupid). Straight Proportional w/2% fee and PPS.
These other payment methods seem to try to reduce flexibility of the miner and are hard to verify. But of course I haven't seen a good explanation of them either.
Sam