Just a heads up for a few people.
Cgminer does not appear to support target rewrites. I have checked the code and the target is derived from midstate and "data" from the getwork. Thus when the pools send you diff 1 work, cgminer ignores that and mines with full difficulty and since the gpu miner code does not check if the hash meets the difficulty, it sends a result anyway. This is why some people have reported they get less shares with cgminer.
For proof, go into findnonce.c and in the precalc function add
printf("nbits %d", blk->nbits);
somewhere, compile and run, it will print the nbits of the current target.
I'd categorize this as a serious flaw. Miners still submitted work, but far less than usual. In the long run, people earned waay less than they should have.
P.S
Conman is aware of this, however is reluctant to fix it. The excuse was "It sends shares, doesn't it?"
