Originally Posted by rfog
However I do not know if it will have zoom options other than portrait/landscape modes...
According to the User Guide, the KDX only has two PDF modes: a) portrait with margins cropped, and b) landscape with continuous pages and margins cropped. Note that in landscape mode the Kindle's screen is about as wide is a letter/A4 page. So this isn't much of a zoom, but it is at least full size.
I would have added a two-column mode where each physical page is split into 4 screens, but Amazon's thinking is obviously that simple is better and that the screen is big enough to allow this.