Does the firmware impact how / if the Hard drive will function (Mac OS X 10.6)?
For the Model WD WDBMYH0010BNC 

I found multiple places that claim it will work on 10.6.8.

http://www.amazon.com/Western-Digital-2-5-Inch-Mainstream-WDBMYH0010BNC-NRSN/dp/B00D901NX6

http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=8433785