PDW for the US Army?

Brickmuppet notes that the US Army seems to be quietly looking at the personal defense weapon (PDW) concept:

A report in today's Jane's Defence Weekly quotes Brigadier General Mark Brown, the head of the US Army's 'Programme Executive Office - Soldier' and commanding general of the Natick Soldier Centre in Massachusetts, as saying that the US Army is looking to acquire a new personal defence weapon: a compact, medium-powered firearm for issue to vehicle crews.
He stated that the new weapon will be "larger than a pistol and smaller than a carbine" and would be employed by personnel not primarily engaged in infantry combat. He said: "When you get all your soldiers geared up in an uparmoured Humvee, there's not a lot of room".
A formal requirement for the PDW is being developed by the Army's main infantry centre at Fort Benning. The small arms centre at Picatinny Arsenal would be tasked to oversee the procurement.
General Brown said that at this point the service has only a "generalised requirement" for a PDW. The report says it is too early to know whether the Army would prefer an off-the-shelf weapon or a developmental item.

XM8's PDW model

Of course, everyone is going to have an opinion on this one. HK MP7? FN P90? Knight's Armament PDW? How about the Bushmaster Armpistol? Or even a pump-action 5.56 pistol? Maybe reissue the M1 Carbine?
Murdoc says "None of the above". This ain't gonna happen.
A major problem is that 9mm-based submachineguns aren't going to be effective against anyone with any armor, and .45 SMGs won't be a whole lot better. Two truly promising little weapons, the MP7 and the P90, use new oddball ammunition and are built across the pond.
I think this is going to wallow around for a while. Then they'll pick either the MP7, the P90, or a snub-barreled M4 and begin development. After a year or two, and a gazillion dollars (or two), the program will be canceled and they'll just issue everyone either a 9mm pistol or an M4. Which is what they're doing today.
Incidentally, the XM8 assault rifle had a nifty little PDW version. That program wallowed around for a while and then died quietly. As will this one.
Call me cynical (or even bitter), and I'm totally shooting from the hip on this one, but I will believe this has a chance when the order for the first 100,000 is issued.
UPDATE: A comment over on my site was too good to not post here:

A hundred years from now, when we are fighting battles on Mars, our troops will be carrying M16's and M9's and bitching that they jam in the Martian dust.

And I thought I was cynical...
-cross-posted by Murdoc
Story Continues