I've got one as well, and I love it to death.
From what I've read, there have been two runs of the OD green 75Bs: the first in 2005, and then again in 2007. I think there were 500 per run (so 1000 total), and only the 2005 ones came with the knife (I may be wrong about that though, I bought mine used so it didn't come with one). The 2005 model should read 9mm Para on the slide, while the 2007 has 9mm Luger instead (they also have the year printed next to the ejection port). Additionally, they both come with a lanyard/dummy cord loop on the base of the frame, though it's easily replaceable if you don't like it.
As Winkel said, they don't pop up that often, so if you like it, hop on it. Personally, I think the OD green is really sharp looking, but still subtle enough to not look tacky, I think you should go for it