I think he is trying to make is that both games are similar because they dont have a monthly fee. This means that you can stop playing the game, and come back four months later, and you still have all of your stuff, without having to go through the hasssle of signing up again and etc.
This is a huge plus for me, as I can only play when I am home on holidays, which makes it frustrating to have to sign up time and time again just to play. I think the reason guild wars has so much appeal is that once you place those first $50 down, the payments are over, and you can play the game without the pressure of having to pay for it.
That is why planeshift appeals to so many players, because it is free, but at the same time isnt one of those crappy 2d games on the internet.