Damn! I've just upgraded the phoenix and while doing this (2 minutes?) the long round ended. Guess what - I got less than HALF of the normal income. I know, its the score, I know. But this really sucks.
My slow 5670 generates a share every about every minute, that means 3 minutes per share up to 3 shares per minute. With respect to the score based system, I get ~0.0005 to ~0.003 BTC per round depending on submission time of the last share. This is a very high jitter though it averages to 0.001BTC in my case.
And yes - it sucks, esp. when the round took about 4 hours and you only get 0.0002BTC.