I plan to do some comparing and contrasting of OneNote versus other note-taking platforms in the coming weeks, but I can faithfully say that I've found what I'm looking for.
Why do I like it, you say?
1. It's pretty. I know that doesn't matter to some people as long as it's not ugly and it's great at what it does, but it matters to me. A lot. In OneNote, you can add notebooks, which go down into tabs that you can color any way you want. Then those tabs can be further subdivided into pages in that tab. Microsoft's stamp is all over the product and it should be - from Calibri font to the famed "ribbon" for formatting at the top. What's weird is that after kicking Office to the curb six years ago, all this doesn't bother me one bit. I will use whatever I deem is the best for me, no matter what company makes it.
2. It does everything Evernote does. From a basic functionality standpoint, OneNote does everything Evernote does for me. It just does it a bit better. I never bought into the tagging system - even with multiple tags on one note, I still didn't feel like everything was organized. With OneNote, everything is categorized into your tabs and then subdivided into your pages if you wish. OneNote is also pretty great in the fact that it lets you type anywhere on the document open, almost giving you a canvas feel to the thing. I can put blocks of text, to-do lists, pictures, and anything else I want to - anywhere I want to.
3. OneNote interfaces with Office much better. If I was an Office user, I would be absolutely giddy over OneNote. It would be a major thing for me. As it stands, I'm not, but OneNote is still a great standalone app for me. It collects everything I need it to, and it syncs to my devices for later use. I can configure what I need to and drop whatever I need to in it. And it will be organized where I want it.
You should give OneNote a try, on the Mac or PC. There are obvious advantages to using OneNote on Windows, and for the low price of free, you can't lose by trying it out. I hear that the Windows Phone app is pretty swell also.
Bottom line: don't change your notes system if it's working for you. Just like the Bible says though: "Test everything." Doesn't mean you have to change your whole process, but it might be a good thing for you to do.