I've read the article, and Kraken's public reply to the request leaves much to be wondered about what it is Kraken is hiding, or what they hope to accomplish by being public about their stance; as for them to say nothing would have had less of an effect on the market as if they were to publicly take a stance.
As someone who has been trading cryptocurrencies for many years across many exchanges (Kraken included) it is in my best interest to seek the exchanges that are transparent about the things NY wishes to learn about. These are, but not limited to:
Transfer and Trading Fees
Planned outages
Insider trading polcies
Margin / Lending market policies
Other related crypto-technology acquisitions
Handling of hard/soft forks of crypto currencies
Hiring of engineering positions meant to support their infastructure (or lack thereof)
While they are under no legal precedent to comply, this is obviously a 'first shot' and will eventually lead to further inquiry by other government sponsored actors that will not be voluntary if they wish to continue operations in the United States.
If cryptocurrencies are to gain mass adoption as a credible way of transferring and crediting wealth; they must be regulated and they must follow a framework to avoid the pitfalls of the current banking system; especially for the institutions that stand to gain per each transaction.
RE: BTC 24% Correction Imminent