If I could sum up the game in one word, it would be "Repetitive". After the initial ooohing and aaahing and trying out all the weapons and vehicles, all that is left is a seemingly endless experience grind. Most of your time online is spent hopping from base to base, spend 15 minutes capturing them, only to see the base you captured before has already taken back. Its a huge game of musical chairs with no incentive to defend bases.
The cone of fire shooting system sounds like a good idea, but it nearly removes all element of skill from the game. In a fight between 2 equal characters, the better skilled one should win. In Planetside, winning is deciding on who has the least lag, or who shot first.
Planetside is definitely not worth a $13 monthly fee, especially when other FPSs provide nearly the same experience (albeit on a smaller scale).