HD Moore posted a great defense of full disclosure in his article The Best Defense is Information on the latest Adobe vulnerability.
The strongest case for information disclosure is when the benefit of releasing the information outweighs the possible risks. In this case, like many others, the bad guys already won. Exploits are already being used in the wild and the fact that the rest of the world is just now taking notice doesn't mean that these are new vulnerabilities. At this point, the best strategy is to raise awareness, distribute the relevant information, and apply pressure on the vendor to release a patch.
Adobe has scheduled the patch for March 11th. If you believe that Symantec notified them on February 12th, this is almost a full month from news of a live exploit to a vendor response. If the vendor involved was Microsoft, the press would be tearing them apart right now. What part of "your customers are being exploited" do they not understand?
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