Looks like yesterday's meeting was just another failed attempt to break the deadlock.
The "agreement" the political leaders reached is practically worth nothing. Washington will not like this. The US is not willing to station people overseas without legal protections...I think it's politically indefensible in the US.
The cause of this deadlock is rooted in the disagreements on power, land and money. All the Iraqi political leaders (except the Sadrists) are willing to vote in favor of immunity, but they will not give this to PM Maliki for free. Specifically, Iraqiya wants the Policies Council and Defense Ministry, while the Kurdistani Alliance wants a friendly oil and gas law [there is coordination on this issue with Iraqiya to reach a mutually accepted draft] and, eventually, some progress on disputed territories. If the Kurds and Iraqiya get these some of these demands, they will support Maliki's request for parliament to give immunity to US troops.
We either get an all-encompassing agreement addressing the issues of power-sharing, oil and gas legislation and US presence, or nothing at all. In other words, Nouri Al-Maliki can't keep both the guns and the money.