I just checked out Midnight Inbox and it looks great. Pretty neat looking. Neat how it collects items automatically.

I'm with the above comment about the Reference system. I have DEVONthink Pro and I'm enjoying using it for what it was designed to do. I don't plan to give up DT Pro anytime soon.

Also, I've been using OmniOutliner Pro for making lists. I bought OOP for kGTD several months ago. I use OOP for different lists I use for GTD and a multitude of other purposes.

One thing I think might be the downfall of Midnight Inbox is that it is trying to do all of GTD. All the vertical levels anyway. While I appreciate this and I think it is a good effort. I just keep thinking, do one thing and do it well. I have lists established in OOP and I don't think I'm going to patch them into one app and tie them up that way.

It seems the GTD-animal would be best tackled with multiple apps for the different purposes. Maybe Omni can get this right and incorporate it with their OOP.

I think Midnight Inbox is a great effort and I'm going to keep an eye on it, but I'm interested to see what Omni comes up with for their OmniFocus. They certainly have created buzz by working with Merlin Mann and Ethan of kGTD fame.

Oh, a feature I really like about Midnight Inbox is the note feature. Click the note type it in and it's placed in the Inbox. Pretty slick... simple, useful, no muss, no fuss...