The more and more I play with the action window, the more I find use with it. With a few extra tweaks to it that have been mentioned elsewhere (back-forward buttons, and a way to jump straight to a section without having to go back to the 'homepage' bit, and a 'lock' so it doesn't auto-resize and you can resize it by hand being the most important imo) the AW will become a really useful addition.
I think this would be great to expand it to encorporate some of the functions that are hidden away in context menus.
The first is the Library Tools - there's some really useful tools in there - lookups to YADb, clean file properties, find & replace, move fields etc, but every time it's right click > library tools > select, which is a bit of a chore. So I suggest a Library Tools section in the AW, which basically has links to this functionality. When you're doing library stuff, you can keep the AW with these tools up, and they're just one click away.
The other is for the columns. At the moment it is not at all obvious how you set up the panes, and even then it's a laborious task adding panes. And there's no ability to move the pane's positions either. Perhaps a 'View' or something in the AW could open up the functionality and allow you to easily select columns, drag them in to the right order etc.
As I say, the more and more I play with the recent interface changes (panes and AW), the more accustomed I get. I think it's definately moving in the right direction here. Nice works guys!