Folder Tracks are one thing that are - to my knowledge - under-developed as to what they have potential to be. I know that in C6 you can slice/move/delete events and mute/solo tracks, but man - that is not enough to say the least! It’s easy and effortless enough to do it even with C5.
But what FOLDER TRACKS really would be great on, is GROUPING and VCA mixing;
For example, one could set up one or several GROUPING ENTRIES onto Folder Track (FT from now on) and associate those entries with several links between the similar parameters of the tracks. This all could be behind the classic E-button in the FT. For example, one could link the EQ2 gain of the tracks 1 and 2 with EQ3 of the track 3 together and name that entry EQ. Or one could link SEND 2 LEVELs on tracks 2, 3 and 4 and name that SEND2LEVEL. All those tracks would of course belong to the same FT.
These entries could be then seen on the drop-down list in the FT. And when selecting an entry to edit, the associated parameters linked could be shown on the Inspector. Selecting an Grouping Entry would also bring up the Slider adjuster and by holding SHIFT key and adjusting with the mouse, it would change the relative values of the linked parameters. Holding down ALT key with the mouse would change the absolute values, and holding down CTRL and clicking would reset the values to their defaults (ie. Gain to 0dB, Q-value to 0.2 and so on).
There could also be an additional editor - named Grouping Editor - which would list all the Grouping Entries on the project as an easily perceivable and editable way. There one could delete/rename/copy&paste (to different FT’s) the Grouping Entries easily. Also there one could link Grouping Entries on separate FT’s together! (And showing the link “chain” icon on the according FT’s). That way it could be easy to, say, lover the gain of the high-shelf of the EQ’s on the tracks that comprise of drums, guitars and synth but have the vocals’ EQ’s unchanged (this would subdue the overall brightness of the background in comparison to vocals to have them cut through better through the mix, just as an example). The possibilities are indefinite!
It goes without saying that Write/Read actions should be utilized there too! One could open up the automation tracks of the Grouping Entries below the FT and edit manually… Imagine how easy it would be to change and automize the properties of several tracks in a few seconds? This eliminates many possibilities for errors when doing that “the hard way”.
VCA mixing: The FT’s could be used as a VCA mixers also: changing, say, volume of the tracks so that the signal that is sent through SENDS, will also be lower (not meaning changing the SEND values but that the actual signal just gets lower). Using Group Tracks this is not possible; If you put a GT volume to -100dB you still can hear the sends’ signals!
OK, I hope I made a point here. In conclusion: The possibilities of fully utilizing the Folder Tracks is endless! Now Steiny; try to put some real importance on them! 
I know everybody has their own aspect on demanding and hoping for features, but I think I have some idea here.