One of the most significant chapters in the history of downloadable content has arrived this morning with the release of Grand Theft Auto IV expansion The Lost and The Damned on Xbox Live Marketplace.

Costing 1600 Microsoft Points, the content offers gameplay equivalent to a third of that seen in the full game, and brings new characters, plotlines and game types to the table.

“The release means the masses of people who already have the original game should be very excited, plus it’s the perfect opportunity for those who haven’t yet experience the greatness of Grand Theft Auto IV to jump in,” Microsoft’s head of gaming and entertainment at its Entertainment and Devices Division Stephen McGill told MCV.

“I think developers have a great attitude towards DLC. If you look at all of the big blockbuster titles of 2008 – Gears of War 2, Fable 2, Fallout 3, Tomb Raider, Guitar Hero World Tour, Lips and Rockband 2 to name but a few – they are all hugely supported by DLC. We’re seeing that developers and publishers are recognising DLC as a great way of extending the life of their titles.

“We see good uplifts of the original games when good DLC comes out, which benefits retail, publishers, developers so everyone should be excited about the opportunities of DLC.”