The report is far from interesting. In fact, it's downright useless. With the exception of one paragraph (below), effects and countermeasures are measured purely in technology avoiding the real effects of IEDs.
In Iraq, small, highly skilled IED cells often hire themselves out to other insurgent groups, such as al-Qaeda in Iraq or the Sunni group Ansaar al Sunna. They advertise their skills on the Internet, and are temporarily contracted on a per-job basis but otherwise remain autonomous. A typical IED terrorist cell consists of six to eight people, including a financier, bomb maker, emplacer, triggerman, spotter, and often a cameraman. Videos of exploding U.S. vehicles and dead Americans are distributed via the Internet to win new supporters.
The first sentence, IEDs cells as mercenaries, is sourced to a Los Angeles Times article from 9/22/06 about the Italians leaving Iraq.
What the report emphasizes is, at least from CRS's point of view, IED's are still simply technological threats and little else.