There is information, unconfirmed at this point, that the United States is about to reach an agreement with Iran concerning Iraq, and perhaps already has.
The gist of the agreement, according to this information, is that Iran will cease to deliver munitions to Iraqis in return for the U.S. agreeing not to bomb or otherwise attack Iran.
There is supposedly also a tacit acknowledgement that Iran will let the U.S. have its troops remain indefinitely in Iraq but at the substantially lower number of 30,000 to 50,000. The withdrawal to that level will be completed, according to the information, by the end of 2008.
Again, this is unconfirmed, and it may not be finalized, but it is believed to be reliable.