I just downloaded and installed the first public build of FBReader and I have to admit to being pretty impressed. It opened a plucker file I have on my 770 and displayed it very nicely, both in normal and full screen mode.

My two greatest problems with Plucker are not there - scrolling and forgetting where you are in the book - which is a major result as far as I am concerned

There's lots of settings to play with, but I have some work to do so that will need to wait but all-in-all a nice addition to the software.