You probably know this, but anyway....
100 real watts (minimum) per plant and an additional 50 real (minimum) watts for every extra plant.
Like Green said, use a mixed spectrum, the plants love it. For flower a 3:1 ratio of 2700K to 6500K bulbs, for veg it's the other way around.
Keep the bulbs close to the top of the canopy, and a little side lighting wouldn't hurt.
To be honest, I've vegged and flowered under CFL's. I couldn't be happier with what came out of veg, flower - not so much. So I've switched my flower to HID, 1,200W HPS and 400W MH, what a friggin difference.
Good luck and have fun.