Warrantless entry?

A recent Supreme Court decision justified warrantless entry by police officers into a person's home if illegal drug activity is merely suspected.  This was an 8-1 decision.

Interestingly enough, the case that was heard came out of Lexington, Ky. According to USA Today, this is what happened:

Officers had entered the breezeway looking for a man who sold crack cocaine to an undercover informant and then fled. Police heard a door slam, but did not know which of two units the suspected dealer had entered. A marijuana odor was coming from one of the doors.

They knocked on that door, announced they were the police, and, hearing noises, broke down the door. They found Hollis King, defendant in Monday's case, and two other people inside with marijuana and cocaine. (The dealer police had chased was in another apartment.)

This is troubling. Granted, the defendant was involved in illegal activity, but does this justify disregard for the 4th Amendment?

Should police officers be allowed to enter someone's private property without a warrant? Does this set a dangerous precedent?