RTM and Todo are both great! I prefer Todo's interface cause some of the buttons aren't so small and so next to each other that it's easy to accidently press the wrong button. Todo's list filters are better as well. I can keep lists on there without some of the lists showing up in my focus list.
RTM has better subtask support with it's ability to have many individual notes under one task, but you can't check those lists off as you could with the actual tasks.
SmartTime is showing great promise for task and schedule management, but it still lacks monthview calendar, something that is a 'must have' if it is to take care of events for me. SmartTime does have monthview calendar coming in an update.
Pocket Informant looks great, but it may not have all the features I need at the time of release (it will get all the features I need in later updates). Syncing to Google and Toodledo was a great idea as both are free services.
Daylite Touch looks to be the ultimate task, project, and calendar app all-in-one. I personally don't need the Project management or contacts features it has, but I really like the look of the interface so far. I'm just wondering how I would back up my data without a Mac computer (I don't have one). Can I back up to Daylite servers and how much would that cost?
Toodledo does have subtasks, but so will Todo in the near future, both require a Pro subscription to Toodledo to be able to have subtasks sync to Toodledo.
@memesmith - check out Daylite Touch's iPhone page, it looks from the app description and screenshots that Daylite Touch will have superb project management tools.