"Stalemate" is the word all of the news and open-source intelligence sources are using for the current Iraq violence situation; I spent some time trying to think of a better term for it, and failed. So I am jumping on the "stalemate" bandwagon, as disappointing as it is to admit that. The stalemate is expressed in a tapering off of the decline in violence; that is, violence in Iraq is no longer decreasing by month; in fact, there was a significant increase in violence in January.
This stalemate is going to pose a great challenge to the yet highly successful General Petraeus and his controversial surge strategy; as the surge ends through the summer, violence might be in danger of increasing should more political reconciliation not occur. This stalemate is showing the urgency for said reconciliation; the security gains made in the last eight months are indeed fragile, and will not remain in the nearly-inevitable 2009 American withdrawal unless sectarian groups feel enough security that they become stakeholders.
A particularly bad sign in all of this is that violence spikes keep occurring when US troops pull out of an area, in particular Baghdad (which absorbed the majority of the US surge). Baghdad might well get hit, and hard, when the surge ends over the summer.
But there is hope. Besides the post-pullout spikes in violence, which seem to be temporary in nature, the vast majority of the violence increases are due to US and Iraqi offensives, rather than sectarian violence or random attacks. One might call this an "investment," like the increase in violence from February to July 2007. Petraeus may be trying to take advantage of the relative peace to use US troops, while they still remain, to root out remaining insurgent strongholds.
In addition, a serious political step may be taken in the next month. Provincial elections have just been approved by the Presidential Council, largely due to very high US political pressure. The elections first happened in 2005, when Sunnis were still boycotting (and de-Sunnification was still the policy of the day), and Sunnis are still woefully under-represented in provincial-level government. The Shiite- and Kurd-dominated executive branch of the government was reluctant to schedule early elections, but finally succumbed. With the "Sunni Renaissance" of participation, as well as the end of the de-Sunnification policy, Sunnis will likely make proportional gains in the provincial-level government, and secure themselves as stakeholders in the Iraqi government. With that, things may well calm down.