I love this, thank you. 
I have a macro to both move selected tracks into a folder and assign them to a new group, now in N8 that new group can be created in that same folder.
To take it to the next level it would be good if the new folder can be renamed automatically to the same as the name i gave the group in the dialog
For example, I have 16 tracks of backing vocals, one key press opens the dialog, I type āBacking vocalsā once , i get my 16 tracks in a folder called backing vocals, assigned to a new group also called backing vocals, and that new group track is placed in the same folder (if i choose) or in the group channels folder as usual.
Not exactly what you are asking for but if you are willing to adapt a little you can already do this using the folowing macro:
Macro - selected tracks to new folder and add group channel
Channel and Track Visibility Agent - show only selected tracks
Navigate - Add Up
Extended Edit - Rename Objects (load preset to rename objects with ābacking vocalsā)
Channel and Track Visibility Agent - show all tracks
This technique has the added advantage that using āEdit/Rename objectsā you can enter standard names like ādrumsā, āstringsā, ābrassā and so on just one time only and save these as presets which can be used across multiple projects.
(Note: this macro works only if you select ācreate outside folderā when you add the group track).