Windows: Microsoft just released Office 2010 RTM today for their TechNet and MSDN subscribers. If you happen to have a MSDN or TechNet subscription, head on over to download what will be the last version of Office 2010 before it's officially released.
(RTM stands for "Release to Manufacturing, meaning it's the version of the software they'll be stamping the installation CDs/DVDs with.)
If you don't have a subscription, you can still download the beta release, which has been available since November. (We don't doubt that there are copies of the RTM floating elsewhere on the internet.) For the rest of us, the official release will be available in June. The Microsoft Office 2010 RTM is available for both 32- or 64-bit Window systems, and is a free download for MSDN and TechNet subscribers only on Windows.