Thanks for the welcome, BassGuitari! For the first point, I figured the Rarity Guide wasn't the end-all, all-complete, all-accurate resource, which is partly why I jumped on here to ask instead of just assuming. Good to know what I figured to be confirmed though. As for your second, dang! It's neat to learn about that sort of thing, and obviously, I wouldn't have thought to notice that difference you pointed out. Now I'm half-tempted to go through my collection again with a finer-tooth comb, so to speak. Granted, they're largely 2's, with my highest ones at a 4, so I ain't holding my breath. Besides, I hunt for games I think I'll have fun playing more than rarity. I largely checked through my games because I accidentally picked up 2 copies of Outlaw and noticed they had different labels, one picture and one text. Alas, it seems likely they're the same rarity, hah.
Now that I'm all signed up on these forums, though, maybe I should hunt for a "Check this first newbs" thread to see where I can possibly go from here...