here is a link to a discussion about the pro and cons of genetically modfied rice... and there is more than one type of modified strain with varying benefits.

http://voices.yahoo.com/advantages-disadvantages-genetically-modified-2064791.html?cat=22

but ir also leaves unanswered the problem of how the food supply can possibly keep up with the increase in population. Malthus should be required reading for every student.