I've been mining on P2P with 760MHs for four days now, but I'm mining just one third, more or less, of what I was getting when I was on a PPS pool.
I do understand that there is variance, but now I need a day where I mine 8 times as much just to be on par with my previous PPS payout.
Given the pool's current/recent hashrate, our average time to find a block should have been about 10-11 hours. So in the past 96 hours, we should have found 9 or 10 blocks. In reality we have found 9 blocks in that time frame.
So, we are pretty much hitting the average. You should have made almost exactly the same amount in the past 4 days as you would have on a PPS pool unless your share-finding-luck has been crazy bad. If you really have seen only 1/3rd as much, something almost has to be wrong because you almost certainly haven't been that unlucky finding shares.
Have you confirmed that your stale rate is not abnormally high relative to the pool?
Are you getting approx the same hashrate as before as reported by p2pool?