This post actually applies to more than just Keynote, but that is what caused me to ask the question:
Apparently (from perhaps a small number of reviewers) Keynote doesn't work as advertised after OS 4.2. For such an expensive ($9.99 - expensive?) ap, you would think that Apple would want to protect its reputation. Does anyone know of any updates to these aps (or the OS itself) that may be in the works?