The Samsung Vibrant (the first of the original Galaxy S devices to hit the U.S.) is no longer supported by CyanogenMod.  According to developer Abhisek Devkota, issues with the way the radio interface layer interacts with the audio layer leads to a loss of the ability to dial 911, and this issue can not be solved without source code from Samsung.  In his own words:

Atinm, the developer responsible for maintaining CyanogenMod on the Samsung Vibrant and Captivate, recently received a free Galaxy S 2 to develop for. (click to see our hands-on).  Don’t adjust your screens, you read it right the first time: Samsung gave a phone to a CyanogenMod developer because they want them to work with it.

We’ve been seeing serious work on getting the GSM flavors of the Samsung Galaxy S line into the CyanogenMod 7 project for about three months, but now it’s officially official — the Samsung Vibrant, Samsung Captivate, and Samsung Galaxy S i9000 have been merged into the CM7 source tree.  Nightlies are currently building, and should be ready for you to test TDR’s bandwidth very shortly.