Not specifically about pets, but I've heard that TNT has gotten faster at freezing stolen accounts. Last year, there was a spate of older (some famous) accounts being stolen -- accounts of savvy users who would never fall for a fake log-in page or other scams; people who are careful about what Neopets-related sites they go to. In many cases, TNT was able to freeze the account within minutes of it being stolen. Though the sheer number created a backlog, accounts were restored relatively quickly (days to a month), and lost items/pets/petpets (though not their age, and not their zapped species
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) were restored within an hour or two of the users reporting the missing items once they were back into their accounts.
A few days ago, I reported someone for harassing me on a Neoboard. They were silenced and the post deleted within 5 minutes. They then came back on a side and tried to harass me some more, though not at a level I felt was reportable (they tried to trick me into leaving a battle against Punchbag Bob with a weak pet a third of a way through, but I knew better). Either someone else reported them or TNT was still monitoring the thread, because their side account's posts went poof within a few minutes.