Documents To Go for iPhone is Available in the App Store
DTG Is now available (special 2 week introductory pricing $4.99, or $9.99 with Exchange integration). This first release has DOC editing only, xls editing is a promised free upgrade. Powerpoint is veiw only, with no mention of future editing capabilities. Additional info soon.
DTG's word processor edits/creates doc, docx, rtf & txt files. The toolbar and screen layout are user friendly, I am finding the learning curve to be lower than that of QuickOffice.