I agree it should be mentioned, it's definitely an additional selling point, so why not? It's actually the reason I even checked the forums. I wanted to know because I lacked it, and even though I already own the game this makes me consider re-buying it on GOG.com. As someone already pointed out, the basic game itself has been re-released to death, but the mission pack was quite a rarity.
I'm a completist, as I'm sure many other GOGonauts are, and having all the official stuff included with the release is one of the many reasons I love to buy from GOG.com. Seems silly not to show it off on the product page :)
Post edited May 04, 2012 by Anamon