I actually totally understand where the TFNers are coming from on this front. When looked at as a six film saga, yeah, it's more or less about Anakin. The focus shifts more to Luke in the OT but I can see where they might be coming from, Luke's story is an essential compliment to Anakin's.

What they're failing to see is that the Star Wars films could be looked at as a saga of something else. PT is about Anakin. OT is about Luke. ST will (hopefully) be about his son. Taken as a whole, these films could be (and hopefully will be) seen as a trilogy of trilogies about the Skywalkers and the galaxy they inhabit. Through this context, the ST is a natural extension of the saga. PT and OT aren't volume 1. PT is volume 1. OT is volume 2. ST is volume 3. And they all make up one large story. That's how I look (or will look) at it anyway, if all goes well.