I've known the delivery took place for some time now, and I have included it in my Iraqi air force report. Guess it's only now since they have been officially entered service, other then training sorties. Although I think they still lack the proper self defense equipment. Once they have that equipment they will be of real value to the coalition effort.
Regarding the US helicopter question, I can give some info, thanks to David C Isby's article in the air forces monthly of June 2007.
In 2005:
142 AH-64
288 UH-60
48 OH-58D
40 AH-1
50-55 CH-46
30-35 CH-53
25-30 UH-1
had been deployed with US forces in Iraq. (not sure if rotational airframes are included...or that they are "order of battle" numbers)
2003-2004: 550.000 combat flight hours
2005: 750.000
2006: 335.000
2007: 400.000
So I guess combining these numbers, gives a rough idea for the helicopters deployed today.
Also the fact that the US withdrew 28 helicopters from Afghanistan, where they are really needed as well, for Iraq also says something about how badly they need them in Iraq.
The Brits have been coping with helicopters shortages as well, however I think more Merlins are available now and the Apache has certainly been a welcome addition. Regarding the Dutch, 3 Chinooks (out of a fleet of 11) replaced 5 Cougars (out of 17)... I think more could be deployed, but it would put a huge strain on the already stretched helicopter group, with also 6 Apaches deployed already. It's time for other NATO allies to commit more helicopters to Afghanistan, now the US is transferring them to Iraq... but I guess most think they are already doing their part with some helicopters and fighters.
Or get new Mi-17s to Afghanistan as well, the Afghans know how to fly them (they actually have some in service)