Earthquake Magnitude

The news articles I have seen about the Haitian earthquakes give a "magnitude" number. I had assumed it was according to the Richter scale, but according to Wikipedia:

http://en.wikipedia.org/wiki/Richter_magnitude_scale

The Richter magnitude scale, also known as the local magnitude (ML) scale, assigns a single number to quantify the amount of seismic energy released by an earthquake. It is a base-10 logarithmic scale obtained by calculating the logarithm of the combined horizontal amplitude of the largest displacement from zero on a Wood–Anderson torsion seismometer output. So, for example, an earthquake that measures 5.0 on the Richter scale has a shaking amplitude 10 times larger than one that measures 4.0. The effective limit of measurement for local magnitude ML is about 6.8.

Though still widely used, the Richter scale has been superseded by the moment magnitude scale, which gives generally similar values.

The energy release of an earthquake, which closely correlates to its destructive power, scales with the 3⁄2 power of the shaking amplitude. Thus, a difference in magnitude of 1.0 is equivalent to a factor of 31.6 ( = (101.0)(3 / 2)) in the energy released; a difference of magnitude of 2.0 is equivalent to a factor of 1000 ( = (102.0)(3 / 2) ) in the energy released.

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The media reports the Haitian earthquake of last week was 7.0, the one most recent aftershock, today, was 5.9
So by the Richter scale, the original earthquake was more than 10 times as strong as the one today.
More exactly [10^7.0 - 10^5.9]/10^5.9 = about 11.6 times as strong
where 10^7.0 is 10 to the 7.0 power.

By the moment magnitude scale, the original earthquake was [10^(7.0-5.9)]^(3/2) = 44.7 times as stong