I've noticed that USA site members often post deals in which games can be bought for $10US under the $60US retail and other similar savings as though they are significant news.

Here in Australia much larger savings are common immediately after launch, even on new copies of games.  Second hand games are cheaper of course.  Prices seem to fall very quickly.  Start at $AU100, deals for around $AU80 fairly quickly, settle around $AU50-70 before finally dropping to $AU30-40 for platinum.

Can someone explain to me what happens in the USA with pricing? 

Do you have EB/Gamestop over there in Oz?

If not, then that's probably why.

second hand games at EB is such a rip-off

I buy them through local independent website, here are the deals I got.
Time Crisis Core 45 bucks

Pretty awesome, right?

We have EB, Game, JB Hi-Fi and then all the department stores with ridiculous prices.

I use ebay. Gamstop and others charge too much for used games.

Usually I can get a $50 for $40 or less about a month after its release. I just sold Zack & Wiki for $24 and Metroid Prime 3 for $37 on Ebay.

Here is what happens for the Wii (and other consoles in general)

A game gets released for $50, and It typically stays that way for 1 year.

EBGames sells used games for roughly $45 until they collect enough stock of that game to drive a price cut on used games, OR the price of the game new drops.

Typically, when a game drops in price it goes down to $30, but this hasn't happened yet on quite a few launch games.

Prices for used games on e-bay and Amazon typically run ~10 cheaper than EBGames.

Stores almost never sell under MSRP, unless they are running some special deal of the day type thing.

Gah come over to England for some really shit pricing..

I got $1 for a yu-gi-oh game that cost me sixty bucks from eb games, because the game was a horrible failure. When I got home, my friend called me and offereed me twenty bucks for it! Arggggg!

HOLY CRAP!!!! That is a LONG time for games to go without a price drop.

The issue is that the major places that have used games is Gamestop/Electronics Botique.

They ALWAYS charge $5 USD under the new price, regardless. Thats why there's such an issue with used games - the majority of new retail stores don't have a used gaming section.