DayZ will be developed as a standalone game, with creator Dean "Rocket" Hall as project lead, according to a statement on the official development site.
Development and updates of the existing Arma II mod will continue in parallel with the development of the game, so anyone who is playing the mod now will be able to continue to do so.
According to the website, the project will follow the Minecraft development model; fast iterations with the community alpha available for a heavily discounted price. Bohemia Interactive will continue to support development.
"I realize people will have many, many questions – but we wanted to let everyone know the announcement now" stated Hall earlier today.
"Over the coming weeks, these questions will be answered. The game will have it’s own site, www.dayzgame.com and the mod will continue at it’s present link."