I do have to say the OmniFocus can be downright fugly and certainly not the easiest program to use.
But I keep coming back to it because I just can't find some of the unique features in the competitors. Let's compare:
* I would personally love to do away with OmniFocus' inspector window and use an inline editor similar to Things or Hit List.
* I'd like to get more robust repeat features (i.e. Repeat on the first and third Wednesday of the month).
Things doesn't have the robust user interface customization that OmniFocus has. All I can see is the ability to change the size of the font. OmniFocus allows me to tweak and customize the font and color scheme to what I want. Granted, I'm too lazy to figure out color and font schemes and I'm fairly sure that most folks just want to use several built-in themes. You can Google for OmniFocus themes and try out a variety of them so that's nice.
I personally found the Asian Efficiency OmniFocus theme very thoughtful with their color scheme. You can see the download link on this page:
I've personally tweaked it a bit further to help differentiate action groups, project groups, and contexts.
It is certainly amazing what a little change can do when you're able to customize the themes. I actually like "The Emperor's New Clothes" when I can change to a different OmniFocus theme.
* I did like that Things and Hit List have some built-in views for Today, Upcoming (Scheduled), Someday/Maybe. OmniFocus doesn't come with these right of the box. I wished that OmniFocus had these perspectives already preset/created and then allow the user to delete these perspectives if desired.
Creating perspectives can be an intimidating feature and is not obvious to the first time user. However, after getting comfortable with creating perspectives, I feel more comfortable with creating my own views for Today, Someday/Maybe, Active, and Upcoming.
Hopefully OmniFocus 2 will come with some preset perspectives and still allow us to create our own perspectives in a more user friendly way.
* Omni Group finally has their cloud syncing service which is free at the moment. I've seen the Hit List does have an option for monthly and yearly fees for cloud syncing. I wouldn't be surprised if Omni does eventually get around to charging for their syncing service. Or they could just try to utilize iCloud. Of course, doing cloud syncing isn't easy. If Apple couldn't get it right with MobileMe, then Omni and other companies are gonna have a heck of a time getting iCloud syncing just right. Even today, I am slowly seeing a trickle of developers finally get their iCloud syncing down and consistently working after a few attempts at getting it to work.
* The biggest feature that keeps me coming back to OmniFocus is the review function. I just can't function without it. The secret sauce to GTD is doing your weekly review - trimming the hedges, cutting the grass, and weeding out all the projects/tasks that are no longer relevant and just cluttering up your project/task list.
I like the ability to set different review intervals for different projects. Some projects only need to be reviewed once a quarter (every 3 months). Other projects can be done on a bi-weekly or weekly basis. This cuts my weekly review time by a lot. I only have to review projects/tasks when I need to. If I wanted to, I can also just review everything to get an overall picture but I rarely find the need to do that.
Using OmniFocus on the iPad actually helped me kickstart the habit of weekly review because the review function on the iPad is so friendly to use.
In Things and Hit List, I'd still have to review everything. There is no way to set reminders to review everything. This either adds considerable time for me to review or I just end up turning numb and just skimming quickly over a long list of projects/tasks and just wish I could get it over with.
I have been tempted to peek at other programs but the weekly review function has kept me firmly in the OmniFocus camp.