I can certainly corroborate the current iPod scarcity
from the perspective of the retail drone. We're still getting dribs and drabs of two or three at a time every few days at work (only 20GBs and minis, usually silver and gold), and are constantly surprised even at that; I keep expecting to be completely out, only to be saved by another one - like today, which put us down to a single 20GB and silver mini. I can't imagine we won't be sold out entirely long before Christmas.
Not that that's necessarily a bad thing, however. An iPod may be an edifying sale - I love proslytizing the virtues of constantly-rotating smart playlists and the brilliantly intuitive interface, so it's genuinely satisfying to make another convert, as it were - but Radio Shack pays on commission, based on profit, not gross sales. Apple leaves very little margin for retailers in their suggested retail price. (I could tell you the exact markup...but then I'd have to kill you. Or something.) As a result, while $427.77 looks nice in gross sales numbers, it's not great for making any money on the actual hardware, compared to high-margin store-brand stuff.
But that's not really the point, is it?