David Berlind has a great piece
based in large measure on an interview with Jonathan Zittrain about the
law enforcement/privacy/tech company flap kicked off by DOJ’s measures
to get Google to comply with their order to turn over search
data. 

Berlind sets it in the right frame, I think, which is not a simple
request for a single set of information to solve a given case or to
stop a crime from happening but rather in the larger context of the
role of technology companies vis-a-vis states in carrying out law
enforcement activities:

“In the bigger picture though (and on the heels of the domestic spying
issue), the warrant for search data, particularly when there isn’t an
investigation into a specific case of wrongdoing, raises more questions
about how far the Feds can and will go when it comes to mining domestic
sources of information that many (including Google, apparently) believe
to be off-limits to the government.  Most US-based Internet users,
for example, use the Internet on the assumption that a record of their
behavior (whether it includes personally identifiable information or
not) won’t fall into government hands.

“Perhaps the most obvious question is ‘where does it end?’  Does
compliance with the DOJ’s request set an ugly precedent that paves the
way for the Feds to comeback for a mile once they’ve taken an inch?
Even if the data that Yahoo, Microsoft, and AOL turned over to the Feds
was uncompromising in terms of privacy, with no particular criminal
investigation taking place, what happens when the Feds see something
they don’t like? Can they just come back for more and take it? Not to
be alarmist or extreme here, but is China — where Yahoo and Microsoft
(also this) have already had anti-democratic run-ins with that nation’s
government — on the other end of the spectrum along which
domestic Internet surveillance policies are shifting and how far along
that spectrum of chilling effects will the US shift?”

(Before reading what Berlind/JZ said, I did an interview with Red Herring on the same topic.)