ONDA 545hd sub-$200 32GB device, 800x480 display, displays TXT files and a pdf ebook reader is in beta. Very bright display for text. It does support bookmarks.
5" screen, comes with a remote, you can connect to your TV in high-def (720p) and takes microSDHC cards. I use it for reading at night now as opposed to my Jetbook and PRS-505. (though now that I found a couple of spare batteries I'm going to get the reb1200 up and running again).
Only issue is that as it came, it did not have a black background - there were a couple of hoops to jump through to make it a black background for ease of reading. Another difficulty is that I need a travel case for it - it is slightly smaller than the jetbook and not able to fit into pockets.
I bought mine from bigboxstore - looks like they are out of the 32GB model right now.