I guess this goes for other ebooks apps, though nothing really comes close to Stanza. It seems like Stanza could really compete with IBooks, especially with its plethora of public domain and other free books, and I wonder if Apple is worried it would hinder its IBooks store.
I've been wondering that myself...I have a whole lot of books on Stanza, and I'd hate to not be able to read them on my yet-to-be-purchased iPad.
Steve said that ALL iPhone apps will run on the iPad. The apps will be displayed in a small window or upscaled on the complete screen. So Stanza, eReader (which I think is WAY better than Stanza), Kindle, B&N, BookShelf, txtr, etc. will all run on the iPad.