Rated 3 out of 5 stars

I'm totally in the habit of quickly adding things I need to look at later to my unsorted bookmarks folder, and using this extension to quickly access them. When it stopped working (in FF4), it totally ruined my work flow. Sooo, time to look for a workaround...

I found (with google, not expertise :-) ), that you can create a new bookmark and set the location as:

place:folder=UNFILED_BOOKMARKS

It might not work straight away, but move it (???) and it will turn into an unsorted bookmarks folder. You can do the same but on the "Bookmarks Toolbar".
Do this with a blank bookmark title and then drag the "Bookmarks Toolbar Items" to the "Navigation Toolbar" (or elsewhere) get something approaching a button (if you don't use the "Bookmarks Toolbar").

Read It Later Rated 5 out of 5 stars

Just to reiterate: "Unsorted Bookmarks Button!" :-)
Currently using the unsorted bookmarks star thingy and this to mimic the functionality I actually used in the old version of "Read It Later". Works well and is pleasingly minimalist.