What swayed the committee was a new FAQ from Sun (which does not seem to be public). In the comments on its vote to abstain, JBoss said in part:
However, while this vote is fundamentally a NO vote, we cast it as an ABSTAIN to acknowledge Sun's role in trying to clarify the situation through their FAQ, and most specifically the central role of persistence in the JSR-220 specification and in the Java platform as a whole: "The new persistence API as defined by JSR 220 will be the standard Java persistence API going forward."
The preface of the new spec draft describes JDO 2.0 as providing JDO customers with a migration path to EJB 3.0, not the other way around:
Similarities between the POJO persistence models of JDO and EJB 3.0 will allow JDO customers
to easily embrace the new EJB 3.0 persistence model . . .
So, JDO 2.0 notwithstanding, JSR 220 (EJB 3.0) will be the standard for Java (J2EE, really) persistence.
For more coverage, see the discussion on The Server Side.