For me, the PD was something of a catalyst. That is, when I read it, it wasn't really one of those "Eureka" moments. It sort of brought together a lot of thoughts and philosophies I already had, but hadn't quite pieced together. It was like, I realized I was always a Discordian. I just hadn't ever had a proper title for it. It crystallized for me so many of the reasons I left the Christian faith of my youth for a more expansive, self-regulated and self-determined religion/spirituality.
As for the book itself, it's been awhile since I've read it. But there are parts that resonate with me in particular and I suspect they are the same passages that resonate with many of you. Nonsense as Salvation, Sermon on Ethics and Love, the Sacred Chao (text)/Reality grids, and of course Greyface.
I still think of myself as a Discordian. I don't really go around telling other people I'm a Discordian. I generally avoid the discussion of religion around friends and family as it doesn't seem to be a very fruitful discussion.
Anyway, not sure where I'm going with this anymore so I'll stop right about here.
This sums up my feelings and past exactly.
As far as philosopies as ladders analogy, I like it but don't think it quite fits.
There are times that instead of it being a ladder it's a compass, showing where to go. Each ideology or philosophy has a compass that points in different directions (with similar ones pointing to similer places). It depends on yourself to know what direction you want. If you go too far in one direction, then you pick up a different philosophy that points closer to the place you want to be.
Now that I've taken that analogy to the breaking point I'll also stop.