I bought the PC version first since the PS3 version was sold out at launch and a PC friend wanted to play together. Was curious what it was like on the PS3 as I would rather play on my big screen TV so I went out to buy the PS3 version as well.
After playing for a month, here is what I found.
Game is designed for a controller for movements and battle. Went out to get a Logitech gamepad on the PC and it works great. Graphics is awsome on the PC - much smoother and sharper looking. Menus and chat is is easier to access.
PS3 version looks pretty decent BUT after playing on the PC with the graphics at maximum, I couldn't go back to play on the PS3. It was more buggy, more laggy and difficult to chat with people as navigating the menus is not intuitive on the PS3. The basic game play is the same but as some others have said, MMOs are just mroe at home on a PC.
Another thing is if after 1 month of free play you think you will stick with this game for the long run (more than a year) then get the lifetime membership on the PC as it will be way cheaper.
One thing you have to be aware of - make sure you turn the auto renew OFF or your account will be auto renewed. I turned that off on the PS3 but didn't realize that the PC version still auto renewed!