Well there is an application, BookZ, that is designed specifically for uploading and reading PG books unto the iPhone and the iTouch.
Personally I don't think Booksontext is going to replace Stanza and bookz for me as a method of reading books. I am not crazy about having to sign in to an app to read a book, and it also generally means that I need to make sure I am near a wifi hotspot when I reach the end of the cached section of a book. Generally, I keep the wifi off on my iTouch except when I am using it.
As for Stanza being hard to read? I haven't found so. You just need to play with it until you find some settings you like.
The iTouch is a really cool gizmo, and I enjoy reading on it.. but it is still a bit cramped. Give me a version with a 6" screen and I will be a very happy camper.