Just updated with this firmware and it looks like .lit is now almost usable. The whitespace problem has gone, although as an earlier poster mentions there's a lack of justified text and I'm not keen on the way the reader seems to fade the last couple of lines of a page. Also there's no page or progress indicators.
It's an improvement, but still not a patch on the fb2 viewer with none of the setting options, really a shame they can't modify that viewer to use for .lit. Still, it's progress, lets hope whoever it is working on this makes some more improvements before too long
I hope the mobipocket viewer returns in a future update too, it was pretty much spot on with the exception of the 4 second page turn delay.