Combat grade is the base level of finish options for Busse combat. It generally means that it comes coated and with standard handles.
CGNMSFNO (combat grade nuclear meltdown special forces natural outlaw) =
Combat Grade - coated, not one of the other grades (competition finish, custom shop, limited edition, special edition)
Nuclear Meltdown - rounded edges and generally longer then it's standard version (in this case the shorter SFNO)
Special Forces - the type of handle pattern used
Natural outlaw - the model/blade shape
Removing the CG from the name doesn't necessarily mean that it's not a Combat Grade edition, but it does require the person to know what they are looking at or further information to know exactly which edition your getting.
-Competition Finish means uncoated with a rough hand finish and with a hand ground thinner edge.
-Limited edition generally means that it's a satin finish and with a special handle type like snakeskin.
-Custom Shop means that it is a custom shop model and will come with the custom shop logo instead of the standard busse combat logo, often times these are satin finished with special handles, but are sometimes coated specially per a customers request.
-Special edition is often attached to a year, 2007, 2008 etc. They most often come with a DCBB (Double Cut Bead Blast) finish and black paper or black g10 handle scales.
here is a link with a collection of the acronyms/qualifiers, as there are many of them
http://www.bladeforums.com/forums/showthread.php/447835-acronyms-list?highlight=acronym+canary