The IRS started this tax season pretty far behind. That kind of delay flows down to the states. So the IRS finalizes their forms and then the states finalize their forms. And then the TurboTax programmers get the forms and have to integrate them into the TurboTax program. Then there is testing to make sure that the newly added forms work with the program properly. Then they are rolled out to the public.
Here is the state form availability schedule for TurboTax