This is definitely not a game for the solo action fan. Planetside emphasis team-based play more than any other major shooter, even Tribes and Battlefield 1942.
It has solid graphics for a MMOFPS, and I was surprised at how smooth it was even in big battles. You'll need a good rig to run it though, and you should definitely have at least 512MB of RAM, and more would be highly recommended.
You're not going to have a good time if you just want to hop on, shoot someone and hop off. Plus, at $13 a month why would you want to when you can play prettier games for free? But if you want to be a part of massive battles with like-minded, hard core action fans, then you should head Planetside.