The BioShock demo has smashed all previous download records on Xbox LIVE by passing the one million mark in just nine days.

The 360 and PC title has also shipped 1.5 million copies.

2K, the publisher, has been using the information to keep investors pumped while the company released its Q3 results, and chairman Strauss Zelnick mentioned that 2K may bring out sequels to the title in two-year cycles, as with the GTA series.

"I'm particularly pleased with the tremendous market response to 2K's BioShock," said Zelnick.

"It is reported we are the top-selling title at GameStop, less than a month since launch. We have already shipped more than 1.5 million units. Clearly we have a new hit franchise on our hands. And this one was developed internally and we own the IP. We're proving our ability to diversify Take-Two's product portfolio."

"We are really pleased that Microsoft's Xbox LIVE Marketplace has managed to attract a record number of gamers to its site to download and check out BioShock," said Christoph Hartmann, president of 2K Games.