I recall reading somewhere that HTC was planning on implementing subs into the game sometime over the next year.
If my information is inaccurate, please correct me.
Meanwhile, what purpose would a sub serve besides Anti-Carrier work? Also, who would have the patience to pilot a sub for hours to get to the last known location of a fleet, only to find it gone?
I just don't get it. With so many other great things to put into an already awesome game, why subs?