1 of our machines is now on Win 7, no problems reported so far.
To be honest, not much difference in performance except for memory.
I did noticed an interesting thing, our UPS is showing power consumption down by 100 watts. I guess it has to do with i7 throttling.
CS3 however was never fully compatible with Vista, so I'm not sure how it will do with Win 7.
Vince Becquiot
Kaptis Studios
San Francisco - Bay Area