Source: http://www.bloody-disgusting.com/review/498
While I mis-read a portion about most of them wanting to be cured, it is a virus/plague, they aren't turned by choice.
"In the film Ethan Hawke plays Edward Dalton, a researcher in the year 2019, in which an unknown plague has transformed the world's population into vampires. As the human population nears extinction, vampires must capture and farm every remaining human, or find a blood substitute before time runs out. However, a covert group of vampires makes a remarkable discovery, one that has the power to save the human race."
"These vampires are fierce, violent, heartless – and worst of all, when they don’t have blood they become horrible creatures of the night. In Daybreakers, vampire become the dominant species and have been capturing humans to harvest blood from. Obviously, they’re running out of blood, so their leader Charles Bromley (played by the incredible Sam Neill) has a research team looking for a synthetic blood to sell on the market. Dalton on the other hand wants a cure."
2nd Source with synopsis and review: http://www.collider.com/2009/09/09/daybreakers-review-tiff-09/
