I've read this recap blog since it started in Season 5 of Lost and I truly believe it's one of the greatest. I think the final recap explains it's better than most. And yes the island did exist and yes, some of them escaped the island and carried their lives on elsewhere. And no, it's not purgatory!
I adore the theme and meaning of the show and still stand by my original opinion "it is, was and will always be, a truly amazing TV show".