Earlier today USCIS announced that it will publish a final rule tomorrow (03.Jan.2013) detailing the new provisional waiver process. We provided some preliminary information about this proposal earlier this year during other coverage of the I-601A provisional waiver. A pre-release version of the rule is available here.
We will continue to monitor this exciting development as new details emerge. USCIS will likely be holding informational conference calls in the coming weeks.