NoteTaker struck me as a winner from its first incarnation, and its evolution has been fast and superb. The "competition" between it and Circus Ponies Notebook seems to me false; although they have a number of basic features in common, Notebook is an elegant, straightforward app which does what it does very well; NoteTaker is far, far more sophisticated. Not that it's complex; it's just powerful. I suppose the analogy would be that NoteBook is a fine high school/college app, whereas NoteTaker will do all that AND take you right up to PhD, post-doctoral level and beyond in terms of its ability to help you co-ordinate really complex projects. The trade-off is that you'll need to spend a bit more time exploring NoteTaker's functionality to get the best out of it. (Not that that's difficult; actually, it's rather fun. Just depends on your attention span, really.)

The new features in 1.8.n include the stunning "X-Ray" facility (hover the mouse over a link and you get a magic preview of what that link contains) and a blindingly fast indexing and searching facility — which sounds trivial but actually ramps up the utility of the tool by, as they say, an order of magnitude.

I'm using NoteTaker as the hub of a large book project which would rankly have been a MAJOR pain, verging on the unwieldy, without it. There are still a few things I'd like to see, but Scott Love and his team are so responsive and so enthusiastic that I'm betting I'll see them implemented before long.

This is one of the pieces of kit which make me not only sure as hell I could never go over to Windows, but also, oddly, proud to use a Mac. (For what it's worth, the others are Mellel, Tinderbox, DEVONthink, Voodoo Pad and Hog Bay Notebook.) When my unfortunate friends who use Windows see the stuff I have on my PowerBook, they feel faintly Jurassic and tetchy.

For the poster who asked about comparison with DEVONthink, I'd say they work superbly together. DEVONthink is more a freeform dump-it-anywhere repository; NoteTaker is a matchlessly good tool once you have a rough idea what you're working on. I have been using DEVONthink to "feed" NoteTaker, with Tinderbox for more complex conceptual plannning. But I have to say NoteTaker is taking on more and more of the DEVONthink functions as it evolves, particularly with its excellent self-contained web search/browse facility. (YMMV, of course).

All in all, unconditionally recommended.