I mine at multiple pools.
Though if I had 50 GPUs, I would be mining solo; being in someone else's pool wouldn't make sense.
How do you set up your own pool? I was curious about this because I'm very near setting up about 127 30mh/s cards (and later upgrading them as profit comes in). Is it as simple as just installing a single bitcoind on one of the computers? (Never done it, completely new to the background of bitcoin processes)
Pretty much what you said. Though that's only 3810 mh/s, which I wouldn't go solo with... I'm curious what cards you're using and how many per rig.
Here is what I will do. I jsut orderd 80 x 6970 to be delivered in slices over the nxt 4 weeks, as initial step.
* I will NOT use deepbit, too expensive.
* I will use a distributing proxy that distributes my load over 2-3 pools on a round robin fashion.
Why 2-3 pools? Because i like to reduce variance

Why not deepbit / pay per share? Because they charge me 10%. Why the heck would I dot that - thigns even out over 2-3 weeks anyway. I am in it for the money, not for paying 10% for smoothing my equity curve.