2 (hopefully) simple yet valuable suggestions
Just a suggestion, and I don't know how easy or difficult it might be to implement, but when a subtask is displayed as the result of a search, it should show the parent task(s). All levels up the hierarchy would be nice for those who use deep layers of nesting, but at
least the next level up would be very helpful. I know the project it belongs to is displayed, but if there are 50 tasks within a project, and some of those tasks have subtasks, it's helpful to see which parent task that subtask belongs to.
To put this in perspective, I'm an independent sales professional for several different and unrelated products and services. Within each service or product line business, I have accounts that I acquire and manage, and each account has actions that are necessary to advance or maintain it. The individual actions I perform relative to an account would clearly be tasks, but then if I want to use the * group feature to represent accounts, I need to see the group that a task belongs to when I find the task via search. A task of "Email Susan the new proposal" would be much more meaningful in the context of "ABC Electronics Account" than simply as an unconnected item that assumes I remember all the details attached to it. There may be many Susans amongst different accounts, and I might not remember by immediately looking at the item which one needs the proposal - that's why I bothered to write it down! ;)
Alternately, using projects to represent accounts could get cumbersome in terms of navigating about from the project view, as well as give me less flexibility to use tags to further manage my accounts. (Such as prospect status, for example)
Also of much help would be the ability to star or flag a task, and the ability to use that as an additional search criterion. As a GTDer, that would give me a quick and easy way to mark my "next action" without having to type out a tag for it, or perhaps to create a "hot list" of items which I plan to work on today (but haven't necessarily assigned a hard and fast DUE DATE of today for.) I'm sure others could come up with additional creative uses of the feature if we had it.
Thanks so much for all your hard work in creating such an awesome product, it definitely fills an otherwise sorely unfilled need!