The relaunch has succeeded to this point sales wise yes. I don't know about in general though or how long they'll be able to maintain the grip they have on Marvel. The creative changes on various books and other nonsense would suggest to me that they've hit a home run but not gone for the cycle. It will be interesting to see where the 52 Verse at this time next year. DC still hasn't as of yet announced any big summer event plans for 2012 and aside from Grant Morrison's Multiversity which I do not believe has anything to do with the 52 Verse...there is probably something planned for their first 52 Verse Event.
I've enjoyed some things but miss the regular DCU. Nothing has blown me away.