"Office Starter 2010 is the Microsoft-designated replacement for its Microsoft Works product. Starter will be a low-end, free (but ad-supported) bundle of Word and Excel.

One (of many) criticisms of Works was that it didn’t support all the same file types as Microsoft Office did, making Works only somewhat compatible with Office. It looks like that same limitation will be present in Office Starter, based on a frequently-asked questions document from Microsoft that one tester forwarded to me. "