Having a personal canon is a big reason a lot of people were able to justify still being Star Wars fans after the huge letdown that were the prequels.

Being able to just ignore those crummy films and build your own PT (as many had already done in the 20some years between Jedi and Menace) from allusions in the OT and in various EU materials has been great for people who can't stand the prequels at all, and now, with The Clone Wars and PT-era comics series and whatnot, though using the same characters and timeline, are frequently better-written, are great for people who like the core essence of the stories of the prequels, but thought they were bungled in execution.