I came to know this from a trusted source.
OPNP is calling applicants and CIC is doing QA to distinguish eligible candidates for Express Entry. Those applicants who are eligible will be automatically added to Express Entry and will be given PR within 6 months i.e., June-July 2015. In this case, applicants don't have to re-apply. CIC will automatically select.
Now, they are doing it for Ontario only because they have 40% of the backlog from Ontario, hence they want to clear this first. That is why they are observing each and every file carefully and therefore, the process is slow.
Those applicants, not selected for EE will be processed at normal speed under original existing category.
Also, maximum applicants of Ontario leave ontario once they get Nomination or PR to get better job opportunities in other provinces. CIC and OPNP wants to make sure that applicants will stay in their designated provinces even after PR.
So guys, no need to worry, CIC is going to clear the backlog very soon in the beginning on the next year and they have already started working on it. Many applicants have started receiving AOR/ME and the process in ON now.
The people who have already applied between MAY-AUG will be given preference in EE and their files will be cleared ASAP.