MacCruiskeen
macrumors 6502
Pretty much this. It would mean I'd be locked into buying books from iBooks.
Not entirely. Only for books that require DRM. iBooks will happily display any non-DRM'd epub-format file. Kobo will too. Kindle won't, unless you run it through a file converter first. Also, if what you want to read is more complex than a novel, the Kindle won't work as well. (This is a drawback of e-ink devices generally--less good handling of graphics and complex formatting. Maybe someday there will be good color e-ink.).