Parallels is to add 3D graphics support to its virtualisation software for running Windows programs on Intel-based Macs. This will let Mac users play top-tier PC games, and could prove a key factor in the Mac versus PC debate (see our Mac, Windows, Linux feature).

Desktop 3.0 for Mac, which Parallels said would launch "in a couple of weeks”, will support both DirectX and OpenGL titles in Windows virtual machines. To prove the point, the company posted a screenshot of Quake 4 running on a Mac.

Among other new features or modifications - Parallels claimed 50 in 3.0 - is something it called SmartSelect, which lets users assign a Mac OS X or Windows application as the default handler for any Mac or Windows file type. Clicking on a file designated with SmartSelect then automatically opens the appropriate application, even if the user is currently not in the application's native operating system.

"With SmartSelect, I set Word for Windows to be my default application to work with .doc, .rtf and .txt files, so when I double-click a file with that extension in either OS - even if it is an email attachment in Apple Mail - the file instantly opens the file in Word [in Windows]," said Ben Rudolph, Parallels' director of communications.

Until the new version is released, Parallels is discounting Version 3.0 50 percent from the usual $79.99 full price in the US, and cutting the cost $10 from the normal upgrade fee.

Some current Parallels users were disappointed by the sudden announcement, which meant the company had skipped public beta testing. "I would encourage Parallels to extend the beta for immediate release and to be more open on development," said an anonymous commenter on the company's blog. "It worked well in the past and made record sales. Why go another route?"

"We were getting overwhelmed by the numbers" of testers in previous rounds of beta and release candidate editions, said Rudolph. "Too many comments were just too general and we weren't getting the focused feedback we needed."

Instead, Parallels has moved to an invitation-only beta process that sets tougher guidelines on such things as the minimum time that users are asked to contribute to testing the product. "The reason why [3.0] is coming out so fast is because we stopped doing public betas," he said.

Parallels' Desktop for Mac is the only virtualisation software tacitly endorsed by Apple and sold through its online store.