I possibly found a problem with list:string field. I´ve searched for a widget and I could found one for it. So I starte to make my own based on this http://blog.crazybeavers.se/wp-content/demos/jquery.tag.editor/ I could be like that tag editor in plugin_wiki too but I found it harder to base on it.
The problem is when you update a field of type list:string using the item1|item2|... syntax it parses correctly and saves like array ['item1','item2'] But if you update the record it shows like ['item1','item2'] and if you simply save it without editing it saves as ['['item1','item2']'] I think the correct would it to reverse parse it to the | syntax, via widget maybe. If it was like this it would be simpler to adpat the above mentioned jQuery plugin. But the way it is it´s need to do two types of parses. Is this really wrong or not?