David,
You may have seen the long thread on the Scrivener forum on the subject of research and writing on the iPad. If not: http://www.literatureandlatte.com/forum/viewtopic.php?f=15&amp;t=7588&amp;hilit=ipad
Towards the end, as I remember, there are lists and mini-reviews of various tools that writers might find useful. (From that thread I'd understood that rtf on the iPad is currently a no-no, apart from Pages and Docs2Go, because of deficiencies in the OS, but maybe that was wrong.)