Within the last few hundred years or so Europe has prospered economically and technologically whereas the Islamic world seems to have faltered. What caused this?
The Muslim scientific age also came to an end because the Mongols invaded the Middle East in the time of the Crusades (the Christians even tried to create an alliance against the Muslims). This destroyed the agricultural and commercial infrastructure in the region that had been building up for thousands of years. Think of the damaged to Europe after WWII and that is basically what the Mongols did to most of the places they invaded. Except the Arabs and the Persians did not have a Medieval Marshall Plan to help them rebuild.
The Mongols also destroyed the library of Baghdad and destroyed most the knowledge that was common in the area by destroying universities, hospitals, banks, libraries, etc. Basically the Black Death in the form of an army of highly organized horse archers and mounted infantry that have no qualms slaughtering entire regions of people if need be.
Hey mate, there's a pretty good list of responses in this thread.