In amendments to the state budget released last week [PDF], the Cuomo administration claims that its $100 million raid on dedicated MTA funds was a one-time deal that won't be repeated in the next three years.
In detailing its plan to close the state's deficit, the budget document lists the $200 million the state took from the MTA (it separately gave $100 million back) as part of the plan for FY 2011-12. For the next three budget years, the document calls for $0 in raids from the MTA.
That isn't really a promise of no future raids. Using funds explicitly intended to support transit to plug the holes in the state budget isn't something the Cuomo administration is going to advertise before it has to.
It is, however, a statement that the state does not currently plan to continue stealing from transit. If one year from now it becomes clear that the state intends to keep raiding the MTA, it will be that much more of a betrayal of transit riders.
Of course, the budget amendments also show a $2.2 billion dollar deficit remaining for next year even including the currently planned cuts. So don't get too optimistic.