http://blog.us.playstation.com/2011/02/16/official-statement-regarding-ps3-circumvention-devices-and-pirated-software/Notice: Unauthorized circumvention devices for the PlayStation 3 system have been recently released by hackers. These devices permit the use of unauthorized or pirated software. Use of such devices or software violates the terms of the “System Software License Agreement for the PlayStation 3 System” and the “Terms of Services and User Agreement” for the PlayStation Network/Qriocity and its Community Code of Conduct provisions. Violation of the System Software Licence Agreement for the PlayStation 3 System invalidates the consumer guarantee for that system. In addition, copying or playing pirated software is a violation of International Copyright Laws. Consumers using circumvention devices or running unauthorized or pirated software will have access to the PlayStation Network and access to Qriocity services through PlayStation 3 system terminated permanently.
To avoid this, consumers must immediately cease use and remove all circumvention devices and delete all unauthorized or pirated software from their PlayStation 3 systems.
Also reports of an email being sent directly to users who have CFW and Homebrew on their machines:
Notice: Unauthorized circumvention devices for the
PlayStation(R)3 system have been recently released by
hackers for the PlayStation(R)3 system. These devices
permit the use of unauthorized or pirated software.
Use of such devices or software violates the terms
of your "System Software License Agreement for the
PlayStation(R)3 System" and the "Terms of Services
and User Agreement" for the PlayStation(R)Network/
Qriocity(TM) and its Community Code of Conduct provisions.
In addition, copying or playing pirated software is
a violation of International Copyright Laws.
A circumvention device and/or unauthorized or pirated
software currently resides on your PlayStation(R)3 system.
Immediately cease use and remove all circumvention devices
and delete all unauthorized or pirated software from your
PlayStation(R)3 system. Failure to do so will result in
termination of your access to the PlayStation(R)Network
and access to Qriocity(TM) services through your
PlayStation(R)3 system.
I added the bold.
Very direct intervention from Sony. The forums are awash with kids screaming "HELPZ!! HOW DO I REMOVE ALL HAX AND WAREZ!1!1!". What I find interesting is that I have heard that Sony have even sent this to people who have not signed in directly to PSN, but have had the PS3 connected to the internet.