We've had (in NY) such a law for a long time now, first in line to pass such a law! There are a lot of counties now that are passing texting laws as well, I don't believe that is a state law (yet).
You can use your cell but it has to be hands-free, no big deal since most phones are bluetooth capable and it certainly is pretty cheap to pick up a headset. The fine is around $100, cheap headset is around $40 yet I am amazed at how many people still drive and hold their phone! I don't think the cops actually pull anyone over for it, just like they seem to ignore no seatbelts or kids not in their car seats.
I don't have a problem with the law, I just think it should be enforced. Based on the number of yakkers I see every day it would be a huge money maker for the state!