I will echo the sentiments of previous posters; I am having a hard time using OmniFocus to implement GTD, and the easiest explanation for other people might be "Oh, he just doesn't know what GTD /really/ is, or he is just a lazy idiot who doesn't know how to review tasks, collect properly, etc."
At one point, sometime back, I made the suggestion to have OmniFocus nag me. I look back with a bit of perspective now and realize how wrong I was. However, I know deep inside of me, that something is definitely not working for me with OmniFocus and GTD. At the very least, the lowest level, couldn't OmniFocus include some sort of user-specific project list that revolves around implementing GTD within OmniFocus?
My ideal situation would involve a couple of things:
1. a "GTD" enable/disable option to give me access to a few handy features
i. Am I collecting, organizing, processing, or doing? This is never clear in OmniFocus (unless I'm in the Inbox or a perspective, but this is arguable), and so, no matter how much I've cleaned up my system, no matter how many times I've edited project and action verbs to reflect the best situation for me, no matter how many times I've optimized contexts, I still come back to OmniFocus an hour later and feel like the whole thing is just kind of, well, dirty. When I finish a massive review of my system, I wanna lock it down. There is nothing more frustrating than seeing Inbox items I haven't processed, so I process them, and it changes current projects, which means I need to go in and edit those projects. This perpetually puts me into Collect/Process/Organize while I'm in the application. I spend a lot of time at the computer for work, and having OmniFocus to fiddle with has been more of a distraction than an organizational tool. I'm not sure how you'd implement this, but I'm begging for some cleaner lines between different types of workflow in OmniFocus. I don't care if it's a simple bar with buttons that do nothing but let me set what mode I'm in.
ii. In different contexts (of the application, not user-created contexts) there should be some GTD specific information. Am I doing a brain dump? If so, I want access to a list of memory joggers so I can really get it all to 0. Am I reviewing projects? I would like a similar system for this. Consider it GTD-related documentation on a per-context basis.
iii. The weekly/daily review is so important, and I feel like it has gotten really weak attention from OF. I want OF to hold my hand and walk me through my review. When I set a date for review, I want to be reminded of it. This brings me to:
iv. I think a number of these scenarios could be controlled in an application/user specific project that is dedicated to GTD. Think of it like this: There is an "OmniFocus GTD" project that mines your database data to give you suggestions, reminders, and due dates for OmniFocus GTD-related actions. If I set a weekly review on Sunday, I want my user-tailored OmniFocus project to say: "Weekly Review - Sunday @OmniFocus Due:Sunday @7:00PM". This means it's not a nag, it's just a project. If I have Inbox items that have been sitting there for a week, I want OmniFocus to say: "Process Inbox [Overdue Inbox] - @OmniFocus". Of course, all of this would be configurable via the preference pane, it wouldn't be annoying, and it would be a MAJOR help to people struggling to implement OmniFocus as their GTD system.
All in all, I'm happy with OmniFocus I suppose, but this whole game we've been playing "It's just an organizational tool" vs "It's kind of supposed to be for GTD, sort of" is getting really tired. A ton of users who bought licenses to OmniFocus did it to implement GTD with their digital life as a compliment to their giant paper filing cabinets. The least OmniGroup can do is give them some kind of support in implementation. It's like "Here's this totally ambiguous app, and you can implement GTD however you'd like! Trust us! You can! It's probably not easy, but who knows, we haven't really tried, it's not really for GTD anyway, but umm, er, I dunno? Good luck!" I'm not asking for a life coach, but not everyone has GTD habits the first time they fire this up, and they need some freaking help.
Cheers,
D