Wishbone: Less competition has never been good for the consumer. Thinking that publishers will lower their prices if they don't "lose" as much money to used sales, is na�ve.
Actually, there's lots of evidence that suggests that the consolidation (and thus less competition) in wireless Internet has helped customers, as it has allowed them to become more efficient and improve coverage, as well as offer lower rates. I'm not sure it's naive, but I think it is a bit foolish to suggest that less competition has never helped the customer.
Wishbone: Yes, DD should be able to offer much lower prices on all games, especially new ones. And yet that doesn't seem to happen. I wonder why not? The thought "let's see, for the DD version we don't have any expenses for production of physical media, printing of manuals, design of covers, shipping and logistics, so why don't we deduct those expenses from the price of the game" is one that would simply never occur to a corporate suit.
I don't know about you, but I picked up several < 1 year old games on Steam for between $5 and $15 during the Steam Summer sale. Furthermore, a part of the reason for high prices in digital distribution (as well as the desire for more money) is the fact that retailers would be very unhappy (i.e. possibly stop shelving their games) if they were being undercut by digital distribution services.
KyleKatarn: Right on. I was going to post something like that, (and I assume CymTyr was going to also) but it didn't seem like it would do any good to argue something like that even though it's true. Personally, I've never seen a game for sale for $10 one year after its release unless it's been a pretty awful game in the first place. Let's also think about three or more years down the road. Unless a game was a bestseller, you can bet that it's probably been discontinued and no longer available in retail, only in used games.
If you look around (CAG is a great source), you can find many "AAA" (although I loathe that term) games on sale for very cheap in a fairly short period after games get released. If you're willing to use DD services, Steam often offers games for very cheap. In addition to their Summer and Winter sales, Valve has also discounted Left 4 Dead and Left 4 Dead 2 75% less than a year after release, and most people would argue that those games are successful.
FrenziedAU: A thought just occurred to me - you don't hear book publishers bitching about secondhand book sales (at least I haven't heard it, and a couple of google searches didn't reveal any bitching).
Books degrade in quality over time, so there's an incentive to getting a new book over a used book. Games, however, do not have the same issues in that regard.