On April 15, 2010, Microsoft announced the release of Office 2010 to manufacturing. This means that the product is complete, and businesses can now purchase the final product. Retail availibility is expected to be in June.
As with Office 2007, 2010 bears ridiculous system requirements. Microsoft recommends at least a 1GHz processor with 512MB RAM and 3.5GB hard drive space. Why? Because of ridiculous amounts of clipart and features that no one uses.
Judging by my testing of the 2010 beta, the only changes are the colour scheme, and the Office button has returned to a file menu (a fancy one at that). I'm sure there's various bug fixes, but Office 2007 is still a perfectly usable product. Upgrading to the latest Office is not recommended. Spend your huge amount of money on something else.