I searched this on google and it didn't turn up any new information so I was wondering if anybody had any information on the recently-formed Detachment One such as their primary missions or any operations they've taken place in in Iraq?

Not alot is known of this unit as well my friend. Very little is released on McDet- as it's known. As you probably already know, they are a compilation of experienced Force Recon/Recon Marines attached to USSOCOM- unknown ops performed in A-stan and the sandbox (Iraq).

MarDet one also has a few other MOS's other than Recon (0321). They
chose Marines from the Intel, CI, EOD and Comm fields aswell....there
probably is a few others, not sure though.

HMMM. So its the smallest Spec ops unit in america?