Just an update to my glowing review earlier. I'm having the same glitch that gouptoo mentions, and it is quite irritating although apparently not causing any serious issue. Sometimes selecting of listed tabs (with CTRL-Click) cause a jump to a random tab from any other group, losing all selections as well. EDITED TO CORRECT THIS, WHICH DOESN'T SEEM TO BE TRUE - [It seems to happen particularly when selecting tabs above (i.e. to the left in the window, as I haven't got the reverse option on), rather than being to do with the number of them. I experimented and found that even selecting one tab above the current one caused it in some cases.] --- I've no idea what conditions it happens under, just seems completely random, and can happen with a single selection above or below.
I'm sorry to report this here, but following the link above supposedly to the support area doesn't seem to give much indication of where to go to report it, and reporting bugs seems a perfectly sensible use of these threads. Still a really useful extension, but I hope this issue can be solved. Do let me know where that is if you'd prefer me to go somewhere else. Thanks.
Suggestion for additional feature: a "Return" - to go back to the last used tab from whatever group you were in. Additionally, perhaps, a little dynamic menu of recently visited tabs could be useful. Dragging and dropping tabs within the same group to re-order them might be good too. To complete the wish-list, if I could quickly put all tabs into bookmarks in their respective group structure, perhaps under a date-stamped folder, or have that happen automatically on a chosen schedule, that would be brilliant.