I've finally fixed the annotation support in Plucker. You can now affix annotations to words in the text. These words are then highlighted, and tapping on the word shows you the editable annotation.
The annotations also function as bookmarks. Actually, to be more precise, bookmarks now simply are special (hidden) annotations. This means that if you install this version, it will convert all your bookmarks to annotations, and then delete your old bookmarks. So make sure that if you try it, you either try it on docs where you don't mind losing your bookmarks, or you have a backup (best both; a backup is always a must; on NVFS devices, you can use my free NVBackup: handpalmstuff.sf.net).
To add an annotation, tap on the bookmark icon, choose "Add annotation", and then tap on a word. Or you can set the Prefs | Lookup option to add an annotation each time you tap on a word.
The annotations are stored in a special database starting with PlkA-. One could write a simple PC program to convert them to text.
I don't know if this version qualifies as beta quality code. It's more like alpha, I think. USE AT YOUR OWN RISK and report bugs at bugs.plkr.org (not this forum).
http://www.plkr.org/snaps