How 'secure' do our homes remain?
How ‘secure’ do our homes remain if police, armed with no warrant, can pound on doors at will and, on hearing sounds indicative of things moving, forcibly enter and search for evidence of unlawful activity?
Justice Ruth Ginsburg via http://www.nytimes.com/2011/05/17/us/17scotus.html

The opinion establishes that action can be predicated on the subjective opinion of an officer as to whether the noise of "movement" is related to criminal activity or the possible destruction of evidence.
What if I am lounging on the couch, watching the Chicago Bulls trounce the Miami Heat and I am in my underwear. There is a banging at the door, the individual(s) identify him/her/themselves as police officers? There is no doubt I am going to run get some clothing on. If that movement is heard outside of the door, officers now can decide to break down my door based on a "suspicion" that evidence is being destroyed merely because they heard movement inside the house/apartment.
I find the 8-1 vote rather surprising as well.