EBgames.com tipped its hand on Xbox 360 preorder bundles yesterday, betting that gamers would be willing to shell out almost $600 to get their hands on an Xbox 360 Core System, four preselected games, and two accessories. Today, longtime competitor and future partner Gamestop.com saw that bet, and raised it $100.

Gamestop.com updated today with four preorder bundles for the Xbox 360, the least expensive of which clocks in at $699.91 for an Xbox Core System, an extra wired controller, a memory unit, a one-year product replacement plan, and five games: Perfect Dark Zero Collector's Edition, Project Gotham Racing 3, Elder Scrolls IV: Oblivion, Dead or Alive 4, and Call of Duty 2.

There's also an Xbox Silver bundle at $799.90, which comes with the premium edition of the console, the same five games, a wireless controller, a play and charge kit, a rechargeable battery pack, and a one-year replacement plan.

The Xbox Gold bundle is the same as the Silver bundle, but it comes with Kameo: Elements of Power and a 12-month subscription card to Xbox Live thrown in. It's going for $899.88 at the moment.

Finally, there's the Xbox Ultimate bundle, where $1,199.83 nets you the same things in the Gold bundle, plus Quake 4, Tony Hawk's American Wasteland, GUN, Condemned, and Madden NFL 06.

Gamestop.com doesn't list a separate price for the product replacement plan, and a brick-and-mortar location GameSpot contacted didn't yet have a specific price on the plan either. As a result, it's difficult to say exactly how much these packages save consumers. However, adding up the elements of the Core bundle, the total retail price would be $669.92, which is minus the one-year product replacement plan. This means consumers would be paying an extra $29.99 for the extended coverage.

Turning to the Silver bundle, the retail price adds up to $771.91, meaning gamers would essentially be paying the extra $27.99 for the product replacement plan.

Interestingly enough, there seems to be no apparent price advantage to the Gold and Ultimate bundles, as the sum of their parts clock in at $871.89 and $1,171.84, respectively, each $27.99 shy of Gamestop.com's asking price for the replacement plan.

After glancing at the bundle descriptions, there's actually a reason not to go with the higher-end packages. Every game and accessory at the moment can be ordered separately, and the product description on the bundles warns that just like with EBgames.com, "GameStop.com reserves the right to substitute any given game in a bundle if that game becomes unavailable at launch." If that happens, Gamestop.com will give customers the option of canceling the order, but it seems to be a take-it-or-leave-it proposition at that point.

[UPDATE] On Thursday, GameStop.com updated its Xbox pre-order page with the new Omega bundle, $1999.69 worth of Xbox 360 games and accessories when money really and truly is no object. For that significant chunk of change, customers get everything in the Ultimate bundle (or should that be the Penultimate bundle?), plus two extra wireless controllers, a wireless network adapter, a memory unit, a replacement "Fuego" faceplate for the system, and more games in the form of Amped 3, Ghost Recon: Advance War Fighter, NBA 2K6, NHL 2K6, Ridge Racer 6, Top Spin 2, Need for Speed: Most Wanted, Tiger Woods 06, and Frame City Killer.

It's important to note that the same game substitution rules are in effect for this bundle as for the normal bundles. Seeing as GameStop.com doesn't list Ghost Recon as shipping until December 1, there's a very good chance that at least one title in every Omega bundle will be a substitute of GameStop's choosing.

Furthermore, when breaking down the cost of the Omega bundle, one finds that once again the customer winds up paying $27.99 for the 1-year warranty, with no apparent incentive for ordering the high-end bundle. [END UPDATE]

Regardless of which bundle Xbox 360 customers choose, or which retailer they go with, it seems the only certainty for the Xbox 360 launch date is that customers will go to bed much, much poorer than when they woke up.