Picked up my newest purchase today.
It is a Rock Island Armory M1911 A1 CS 45 caliber pistol. It is the smaller frame version of the 45, known as an Officer's model. It has a 3.5inch bull barrel, skeletonized hammer, beaver tail, and a shorter grip then a full sized Government 45.

Here it is next to my full size Rock Island 45.

I've ordered a set of Hogue grips for it, I don't care much for the wood grips. Hoping to put a couple boxes of ammo through it next weekend, but if it shoots anything like the full size pistol, I'm going to love it!
EDIT: Just realized that the magazine in the photo isn't the one that came with the pistol. It is an older mag that I already had for another pistol. It is a shorter, 6 round mag, designed to fit the Officer sized 45 and fits the new pistol. The magazine that it came with holds 7 rounds.