This is wrong. Most of the polls show that the Sith Inquisitor and the Bounty Hunter are the most popular classes. They also say that the SI class story is one of the worst, second only to the Jedi Consular's class story.
Yes, SI will be over populated. Yes, Empire will most likely be full of FotM kiddies who want to be Darth Maul, Boba Fett, or the Emperor.