I've been really annoyed by the fact that one needs to swipe to switch pages in Overdrive, and I think the Kindle app also had the same issue. So I modified my mod of the Gingerbread keyboard to do paging in Overdrive and Kindle by pressing volume up/down, in the way that works in all decent ebook readers. :-)
If you want other apps to have this, let me know and I'll add them.
Eventually, I might add customization as to which apps get this.
http://code.google.com/p/oc-gb-keyboard/downloads/list
Alas, this won't work if you have some other favorite input method.
To use this, you need to enable the Gingerbread Keyboard in the device's Input Settings, and then you need to select the Gingerbread Keyboard as your input method, by long-tapping on an input field in some app.