Microsoft has detailed Office 2010 information in regards to the 32-bit and 64-bit versions, including the fact that both will come on the same DVD.
Full Story: http://arstechnica.com/microsoft/news/2009/07/confirmed-office-2010-32-bit-and-64-bit-coming-on-one-dvd.ars
Full Story: http://arstechnica.com/microsoft/news/2009/07/confirmed-office-2010-32-bit-and-64-bit-coming-on-one-dvd.ars