Clearly, unusual, unheard of events like tornadoes in Kansas, Tiger Woods playing well at the Masters, etc. are signs of the End Times.
There has been an ongoing question among prophecy scholars about the relevance of recent earthquake activity, but this recent great quake (measuring 9.0 magnitude) in the Indian Ocean, and the ensuing tsunamis, is too great to ignore. It caused unimaginable death figures from eleven nations in Asia and Africa.
Some are calling it the greatest known natural disaster. The death toll had passed 140,000 by the end of the year and is still climbing. There is no reason to relate this catastrophe to the fulfillment of a particular prophecy or to see it as an act of judgment, but it does at least call attention to the fact that Jesus said there would be great earthquakes in these last days.
According to Revelation 6:14; 16:18-20, a very great earthquake will occur as part of the Battle of Armageddon at the end of the Tribulation period. During this earthquake every mountain will be shaken down and every island will sink.