[Forrest]

Doesn't look too bad. I like the idea when depicted that way. I really dislike stacks, they are practically useless and create disorganization that we don't normally see on a computer because computers have always been around to make things easier.

But what you've created is more just organization of tabs in folders. It could use a little color coding or indenting or some other visual cue as to what tabs belong to which folder. But if Photoshop is any indication, the addition of groups in the layers pallet has been a huge help and I think the same would be true for tabs.

[PeeM]

Yeah it would just make things easier for people who like to use it, others won't mind/recognize. It's like the folders in iTunes for playlists...

[erikswanson]

On a slight tangent, one feature that might be useful would be a way to quickly collect all tabs for a given domain/site into a new (or the current) window.