noted that Sun's StarOffice suite of productivity tools has been added to the free Google Pack offering. StarOffice is a direct competitor to Microsoft Office, as it is a full suite of desktop-based office apps that normally retails for $70. It includes word processing, spreadsheet, presentation, drawing and database. It has support for most Microsoft Office formats, except for the formats introduced in Office 2007. It is however only available to Windows users.The Google Operating System blog
As Google Operating System pointed out, Google is not using OpenOffice; an open source project sponsored by Sun based on StarOffice's source code, released in 2000. GOS states that "the primary difference between StarOffice and OpenOffice.org [is] that StarOffice includes some proprietary components like clip-art graphics, fonts, templates and tools for Microsoft Office migration."
This agreement has been a long time coming. Google Pack was launched back in January 2006 and even at that time there were suggestions that OpenOffice would soon be added. John Battelle interviewed Marissa Mayer, Google's Vice President of Search Product and User Experience, at the time and quoted her as saying: "We realize software distribution will have to become one of our core competencies".
Image from Google Operating System
The addition of StarOffice to Google Pack suggests an extension of the existing agreement between Google and Sun, who both have a lot to gain - Google gets a full desktop-based suite to complement its growing Web Office offering, while Sun gets a lot more (mainstream) users care of the distribution in Google Pack. As noted in the joint Google-Sun press release in October 2005, the two companies "agreed to explore opportunities to promote and enhance Sun technologies, like the Java Runtime Environment and the OpenOffice.org productivity suite". My guess is that Google is using StarOffice and not OpenOffice as a concession to Sun - possibly explaining why it's taken 1.5 years to come to an agreement to add it to Google Pack. Certainly Sun will be all smiles with this, as it increases their brand and means they have more influence over the future of desktop office software.
As always, it's a smart move by Google on a number of fronts: 1) it nicely complements - and covers gaps in - their online browser-based office products; 2) it enhances their credentials as a software distrbution company - and remember that software distribution over the Internet is a key part of Microsoft's Windows Live initiative (they call it "software as a service"); and 3) it points to more online/offline syncing, or as GOS nicely put it: "the next step would probably be the addition of a plug-in that lets you synchronize local documents with Google Docs & Spreadsheets, so you can have the best of the both worlds".
Also Google makes no bones about this being a competitive move against Microsoft. The Google help page on StarOffice states: "With StarOffice, you can easily view, edit, and save Microsoft Office compatible files."