If you're using a database I recommend you check your SQL logs before getting in too much of a panic. Could just be that you have some slow-running queries that need to be tuned.

Then again, I also agree with the comments that it could be your content making them nervous. You might carefully read the TOS to make sure you're within guidelines. If you're on the edge, they might be using IO as a simpler excuse than trying to enforce gray areas in the TOS.

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Ron http://www.chalicemedia.com Distributed Creative Content Architecture