This is the kind of good news that only illuminates how terrible your problems are. Yeah, it's cracking that the Iraqi spooks (supposedly) got to hear about a plot for the Final Shootout, but it's pretty bad news that the speaker of parliament's bodyguards were behind it.
Worse, it looks like a hell of a plot. Apparently a multiple VBIED attack was planned inside the Green Zone, aiming to decapitate the government, whilst simultaneously an Islamic Emirate would be proclaimed next door in Diyala Province, on Eid ul-Fitr, and a pogrom against Shi'ites launched. It could well have worked, at least initially - the major fault being that the Diyala phase of the plot would have meant instant war with the Kurds, who have territory in Diyala in striking distance of Baghdad. And the plot would probably have killed the Kurdish president of Iraq, Jalal Talabani.
The Sunni, though, despite couping, would stand to lose a lot - SCIRI would surely go ape and ethnically cleanse most of Baghdad. So why was it Dulaimi's lot?