Microsoft has now made available a 90-day free trial version of Windows 7 (RTM), called the Windows 7 Enterprise 90-day Trial version. It is intended to be downloaded by IT professionals -- the good news is though, that just as long as you believe yourself to qualify as an IT professional, you can download it.

The Windows 7 Enterprise 90-day Trial will be available until March 31st, 2010 -- or until they run out of an unspecified amount of license keys available. The 'Enterprise' version is pretty much the same, feature-wise, as the Ultimate retail version.

The trial Windows version comes in 32-bit and 64-bit flavors, and five of the world's most popular languages.

On the Microsoft download page, it says that once this version of Windows expires, you will need to do a fresh re-install of the OS. However some of said that it is possible to change product keys -- so if you decided to purchase Windows 7, perhaps you might be able to change your key, thereby saving yourself the hassle of having to re-install an OS.