Open Question: Obama's health care plan, pre existing conditions and insurances?

I have a very serious chronic illness and my wife as well and I am working in a company now that I did not want to leave because I was afraid that if I get a new insurance in a new job they will decline me and my wife for pre existing conditions. Now my question is, with the new laws or rules of the health care bill that no insurances can deny you coverage for pre existing conditions is that applicable already or will be applicable when the new health care system starts running and if so when will that be?