It has just been updated to version 1.0 after a rapid evolution, and now sells for $19.95. I tried some of the earlier versions about 0.8-0.9, and at that time, the iCal sync was not perfectly stable. Can't comment now, but almost certainly better. Ghost Action puts the project name in brackets at the end of the item in iCal, as in "Visit Mercenaries R Us [Invade Albania]." When I first saw that feature, I thought it would be nifty, because Agendus, a Palm application, will interpret whatever is in brackets as a contact (the old projects as contacts ploy). I soon tired of the [brackets], finding that I now prefer a stripped-down, vanilla implementation. Ghost Action competes in the same space as Actiontastic and EasyTask, and the much-heralded OmniFocus.
The three programs that are released all have misfeatures and bugs, but are workable. One thing I find seriously annoying is that they all treat a project as just a label, with no place to store project notes. You can work around this, of course, but it's stupid.