I really can't see the problem... Even reading a 'normal' (pbook) creates an interruption in reading...A scroll would be perfect..
My palm Zire72 has an immediate refresh, much faster than a pbook, but the screen is very small, and I honestly don't have a problem with the refresh rate on my kindle... On my Hanvon, the screen doesn't go black, but the new page comes up slower than on the kindle.