Well, to be fair, it's admitted in the book that the systems are intentionally similar. The first psionics were introduced was I believe in version 2, where they were handled totally differently and were, to be honest, broken as hell. They took a look at that, removed them entirely from version 3.0, and then eventually added them back as a re-balanced expansion. I have 3.5, which is further re-balanced, and I'm pretty sure Barrel and I have the same book from how he's talking. The reason it's similar to magic is that it uses the same basic framework, but provides a different set of abilities to work with and a new set of classes with additional mechanics, such as the Wilder's ability to essentially do a Limit Break at will or the Wilder and Psion's ability to generate a Psicrystal to act as an extension of their own body for casting purposes and provide bonuses and other abilities.

My problem is that 90% of "psionics" is just the regular magic system with new names and they had the gall to sell it to me when the new info could have been contained in a couple of pages.

Think of it this way, that's more than can be said for textbooks, and they're ten times as expensive. :p