The Chilean earthquake was an 8.8, and I think the Haitian earthquake was a 7.7, so it's about 10 times more powerful because it goes by a logarithmic scale.
Still, any earthquake is bad.
The scale doesn't work that way. I'm not an expert but according to the news info I've read it was 500 times more powerful.
ABCNews.com quote,"The earthquake, which hit just after 3 a.m. local time, was 500 times larger than the one that devastated Haiti last month but was much deeper, likely making the number of casualties far fewer than those in the Caribbean nation."
Foxnews.com quote, "In terms of energy released at the epicenter, the Chilean quake was 501 times stronger. But energy dissipates rather quickly as distances grow from epicenters — and the ground beneath Port-au-Prince is less stable by comparison and "shakes like jelly," says University of Miami geologist Tim Dixon."
Also the building structures in Haiti were much weaker than in Chile. The better constructed buildings in Chile, for the most part, helped too.