Vista beta goes public

After months of limited testing, Microsoft late on Wednesday made a beta version of Windows Vista publicly available for download.

The company kicked off what it called its "Customer Preview Program", a testing period in which the software maker hopes millions of tech enthusiasts will kick the tyres on the new operating system.

The company said in a statement: "Microsoft today kicked off the Windows Vista Customer Preview Program (CPP), providing the broadest access yet to pre-release test versions of Windows Vista."

Microsoft is aiming to wrap up testing and development of Vista later this year in the hopes of a broad launch in January. The company released Beta 2 last month to a more limited group of testers and had promised the broader test would come shortly.

The software maker is still cautioning that Vista is not ready for the average consumer, pitching the CPP as suited for developers and tech workers, as well as hard-core enthusiasts who don't mind a few bugs and have a spare machine for testing. Microsoft also recommends those interested in the CPP run its recently released adviser tool, which helps detect how Vista-ready a PC is.

People can either download the software from Microsoft's website or pay a small fee to get it on DVD.

Although Microsoft is looking for millions of testers, it has said it may cap the test programme at some point.

Ina Fried writes for CNET News.com