The reason for this move is that we could not establish a reasonable degree of interoperability with OpenOffice ODF unless Sun supported the five generic eXtensions to ODF needed to hit the high fidelity conversion the da Vinci process is capable of.
Since da Vinci is a clone of the MSOffice OOXML compatibility Kit, we use the same internal conversion process where imbr (in-memory-binary-representation) is converted to another format: imbr <> OOXML or, imbr <> RTF.
While it's entirely compliant to eXtend ODF, without Sun's changes to OpenOffice ODF the application-platform-vendor independent interoperability end users expect would be meaningless.
The problem as we see it is this; it is impossible to do a high fidelity conversion between two application specific XML formats.
It is however quite possible to do a conversion between an application specific format and a generic (application-platform-vendor independent) format.