When Wikipedia changed licences they talked to the FSF to arrange an upgrade path. Perhaps you and the Open Data Commons people should get together to thrash out an 'open map data licence' acceptable to both. It could then be published by both organizations as an upgrade to CC-BY-SA 2.0 and ODbL 1.0 respectively. The licence change problems of OSM would then disappear (and many people, like me, who have opposed the change partly because they did not want to abandon Creative Commons, would likely accept the compromise).
One root of the disagreements is an attempt to treat an online map as abstract 'factual data' like a telephone directory. It isn't quite like that, not legally, and certainly not in the perceptions of contributors, who feel they are making a collaborative work just as much as Wikipedia. For that reason a 'computer cartography licence' might be a better fit than something purely about abstract 'data'.