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1) A lot of the former url's for Place Pages or Business listings are now changed to the new url format of Place pages.
And, surprisingly, the old cid=12345 url doesn't redirect. I just get a "We currently do not support the location" error on G maps at the old url.
There's still quite a few that have the permalink as the old url format but a definite shift toward the new url format that was unveiled in the Google announcement on Place Pages [googleblog.blogspot.com].
2) Quite a few websites that I've verified in the past are showing new duplicate listings. G's had an issue with properly conflating listing for a while (at least since Feb 09) but it seems worse in just the past couple days. It also seems to only affect sites that have been claimed.
My guess is that we're seeing some weirdness due to the move to the new Place Page url structure. After researching these issues, I'm going to try to be patient & wait it out for a few days... see if everything just falls into place.