Both the MSDN (Microsoft Developer Network) and TechNet sites now host the Office 2010 Beta in 32 and 64bit editions, which can be downloaded by the developers and IT professionals who have subscriptions to those services.
TechNet, for example, has posted the downloads here (Windows Live ID login required), while the MSDN site sports a message saying that the beta is now available.
The TechNet downloads are for Office Professional Plus 2010, an edition that will be available only to enterprises and organisations that purchase licences in volume.
Other builds of the Office 2010 Beta, which have already leaked to the internet, can be found on numerous file-sharing sites.
Microsoft is expected to open the beta to all users sometime this week. It has already prepped a revamped version of its Office.com site - still in beta at time of writing - to offer three different editions , including the consumer-oriented Home and Business 2010.
The company has also posted additional information about the beta, including the hardware requirements necessary to run its newest suite, on its web properties.
Microsoft will provide previews of three of the five editions it intends to ship in the first half of 2010: Home and Business, Professional and Professional Plus. The first two will be available at retail.
Last week, Microsoft shut down its earlier test, dubbed 'Technical Preview', and told users running that version to expect news of the public beta this week.
Microsoft kicks off its annual Professional Developers Conference (PDC) in Los Angeles today, and is expected to use that forum to unveil the public beta.