BBC reports (with video),

Supporters of Shia cleric Moqtada Sadr have staged a mass demonstration in Baghdad in protest against plans to extend the US mandate in Iraq.

An estimated 50,000 protesters chanted slogans such as "Get out occupier!".

Sadr's message was

anybody who says the agreement will end "the occupation of our land" or "tells you that it gives Iraqi sovereignty is a liar."...

Clerics led crowds of people who waved Iraqi flags and chanted slogans including "no, no to the agreement" and "yes to Iraq."...

"Get out occupier! We demand an end to the occupation!" shouted the crowd of people, some of them draped in Iraqi flags.

Sadr's supporters in the Iraqi Parliament are adamantly opposed to the deal:

"I won't vote for this agreement as it stands, and anyone who would is a traitor to the Iraqi people," said Bahaa al Araji, a lawmaker with the Sadrists, followers of radical Shiite cleric Muqtada al Sadr. "Many of the points included in the draft I read are contrary to the Iraqi Constitution and Iraqi law." 

Others in Parliament are hesitant to support the proposal because of upcoming elections:

Upcoming elections in Iraq also could complicate matters, said Salim Abduallah al Juburi, a spokesman for parliament's largest Sunni bloc.

"Unfortunately, not everyone will look at the agreement from the point of view of what is best for Iraq," he said. "With the elections, some will think only about the impression their decision might have on voters."

Representative democracy at work - imagine that!

Iran's behind-the-scenes role is highly controversial. Sunni's always blame Iran first:

Mithal al Alusi, a secular Sunni Muslim member of parliament, said he'd support the draft if it made it to a vote in parliament. But, he added, "There are many who could oppose it because they are agents of Iran. It will ultimately be a fight between true Iraqi patriots and those who have been taken over by the Iranians."

But when the U.S. commander in Iraq, Gen. Ray Odierno, said the same thing to the Pentagon Post, Maliki was outraged and threatened to get him fired:

"The American commander risked his position when he talked about this issue and in this manner. He has regretfully made relations complex," Maliki said in remarks made to Kuwaiti journalists on Thursday and aired Friday.

The text of the agreement still has not appeared either in English or Arabic, but a little more detail on the immunity provision was leaked:

In most cases, U.S. forces are exempt from Iraqi law while on combat missions or on bases. However, under the accord, if a soldier commits an act that could be considered a premeditated crime or gross negligence against an Iraqi, U.S. and Iraqi sides would convene a committee to decide whether the case should be referred to an Iraqi court, a senior Iraqi official has said.

U.S. officials are speaking with forked tongues, telling Iraqis they will have "first shot" at such prosecutions while telling Congress the U.S. will "have the final decision." Since those are mutually exclusive, we won't know the truth until the text is published in both languages.