[punkadiddle]

I just started to use the cover grid to browse a library books and I was wondering if there's any way of quickly editing some of the metadata.

Is it possible to display the list view synchronized next to the cover grid to use it as editor? I have a pretty wide screen ;-)

I manage my photos using Adobe Lightroom. There's a photo grid and I can use the keys 0-5 to set a picture rating, X to mark a picture as discarded and another key to mark a picture as good etc. It's very simple and efficient. With the custom fields in calibre an equivalent could be metadata templates plus custom shortcuts.
Is there any way to accomplish quick editing (especially in the grid view)?

I know I can create an ad-hoc collection of books by using markers. But there's just a single type of marker.