GameStop, a leading US retailer, is currently listing Rockstar's first portion of Xbox 360 exclusive DLC for GTA IV at a price of $20 (or 1600 Microsoft Points, £13.60).

If true, this would be the first time that a publisher has simultaneously distributed DLC both over Xbox Live and as a boxed code at retail.

"Grand Theft Auto: The Lost and Damned packaging will include a 2 sided poster and an Xbox LIVE Marketplace token card," the product listing explains. "The token card will contain a unique code to purchase The Lost and Damned over the Xbox LIVE Marketplace."

We've contacted Rockstar on the matter and were told that until we hear anything further from them, we should take any other information with a pinch of salt.

It seems unlikely that GameStop's listing is bogus, but it's also hard to tell whether the pricing at retail will be the same as it is over Xbox Live. Nevertheless, at least this $20 price tag gives us a ball park figure for next year's hotly anticipated DLC.