I can't remember for sure, but I think I read about PS in Macworld magazine about 4 years ago and it sounded interesting, so I decided to give it a try. There were almost no other Mac playable MMORPGs to choose from back then, and certainly no free ones.
I made a char. and played maybe 4 months, but many problems with places too dark to see at all in and then updates where Mac clients were not available for long periods of time afterward made me give up. In fall of 2008 I decided to give it another try and even though after one day of play and another update taking 3 months before a Mac client was available, I've kept playing since. Even though lots more Mac games are around now, I haven't found anything I like as much as PS since I mostly like RP.