You can see the past draw details here --- http://www.cic.gc.ca/english/express-entry/rounds.asp
As you can see, the last draw had a cutoff of 755 and the lowest cutoff so far has been 453. No one really knows what the cutoff would be in the future - the only thing left to do is to maximize your score by doing an ECA for education, (re)taking language tests, trying to get a provincial nomination or an LMIA supported job, and waiting... All the best!