What's their angle in all this? We've all known for years about the bitterness between IBM and Microsoft, so it's possible IBM wants OpenOffice to succeed over MS Office or perhaps reach markets that MS Office can't. The OO.org Marketing Project Lead hopes IBM will deploy ISO ODF standards elsewhere, which could help adoption in the enteprise market where IBM reigns:
“We welcome IBM's contributions to further enhancing the OpenOffice.org product. But equally important is IBM's future commitment to package and distribute new works that leverage OpenOffice.org technology supporting the ISO ODF standard. ODF is a once in a generation opportunity for the IT industry to unify round a standard, and deliver lasting benefit to users of desktop technology.”
It doesn't appear that IBM will be offering any financial support to OO development, but code development is crucial. You can read the full press release at the OpenOffice.org site.