From the Guardian, Saturday 26 January 2013 11.48 EST:

By late Saturday morning, the USSC website was offline, but cached versions could be found where the message appeared.

Anonymous, which has been the target of numerous arrests and FBI probes, has taken a relatively high profile in several cases recently. In the small Ohio town of Steubenville, which has been rocked by rape allegations against several high school football players, the group has organised protests and posted evidence it says shows evidence of a cover-up of the alleged crimes.

Anonymous is a loosely defined collective of so-called hacktivists who oppose attempts to limit internet freedoms.  It has suffered from some high-profile arrests after attempts in recent years to attack major corporate government websites.

Swartz and Anonymous have been firm advocates of open access to information and open-source programming. At a memorial service for Swartz last weekend, several of his supporters called for those who were attempting to prosecute him to be held accountable for their actions.

Swartz had faced a possible jail sentence of 30 years, though it has since emerged he was also offered a plea deal of six months.  Officials involved in prosecuting the case have insisted they did not over-reach in their aggressive pursuit of Swartz but have faced a storm of criticism for their behaviour.

The text from the youtube video page:

Published on Jan 26, 2013

USSC.GOV HACKED!!! — This time there will be Change or there will be Chaos.
#WarHead1 — Download Encrypted Files
pastebin.com/d2nvt263 — READ THIS!!!
Create a Video Response — Tell the US Government how you feel.
Http://goo.gl/PUDDZ — Spread this Video to anyone, anywhere, anytime, anyhow
http://www.youtu.be/_bAMgFt9z4Q — Reason
pastebin.com/d2nvt263 — READ THIS!!!
http://goo.gl/tv55L — Join #OpLastResort-TwitterStorm and Help Finish Aarons Work
(Also, Report spam about “Real Warheads” to IRC for removal)
pastebin.com/d2nvt263 — Download & Mirror some encrypted #WarHead1 files.

Knowledge is Free.
The Corrupt Fear us.
The Honest Support us.
The Heroic Join us.
We are Anonymous.
We are Legion.
We do not Forgive.
We do not Forget.
Expect us.

A comment under the video reads:

Gabrielregalado2 27 minutes ago

“He didnt commit suicide you noob, according to wikileaks, he was one of their informants, thats why he got killed.

Dont eat all the shit the government puts on your plate”

?????

Also at the Guardian:

Anonymous hackers jailed for cyber attacks

Two men jailed for carrying out cyber attacks, including one online assault that cost payments giant PayPal at least £3.5m.

I confess ignorance about any and all of this; if you have questions, it’s a guarantee I won’t have answers.  You may, so help us out if you can.