I generally share willcarter's concerns when a good app starts adding features and begins to feel as if it's getting off track. But in this case - adding filters to OO - I truly think this is a change that puts OO deeper into its own groove. It fulfills the promise of OO.

Filters extend the abilities of lists and outlines. Many of us who used to use Ecco Pro know full well how incredibly versatile an outliner can be with this one simple addition. It doesn't try to ape a database - it makes a simple outline a far more useful tool.

If a user doesn't want filters, they never have to even see them. But my strong belief is that once users see what filters can do for an outline, they'll find a lot more uses for them.

For me, a database program is overkill and far more complex than what I need. An outliner like Ecco was exactly the right tool for a wide variety of lists and projects. Far more than OO. And the difference is filters.

Think of OmniFocus without Perspectives. It wouldn't be anywhere near as useful. If we ever do get filters for OO, and you start to use them, you'll never want an outliner without them.

TaskPaper has a very idiosyncratic form of filters, it might be work a look if it's a must-have.

+1 for filters a la Omnifocus

Another vote for filters. Like what all the positive voices have been sayin'!