I started to use Evernote about two years ago because it came as part of a bundle of Mac applications I purchased. Well, Evernote is free, obviously, but the bundle included a year of the premium upgrade.
As others here have said, I’m not particularly emotionally invested in Evernote, so I’m not sure I understand the Kool-Aid angle. I use it pretty simply. I always have a few different creative projects going on at once, and I’m not exactly the world’s most organized person under the best of circumstances, so it’s nice to have a central repository where I can jot down notes, thoughts, ideas, sketches (their iPad drawing/handwriting app Penultimate works great and auto-syncs with Evernote), photos, etc., no matter where I am - whether I’m out and about with my phone, sitting in front of the computer, or lounging on the beach with my iPad (which I realize all sounds like bad first-draft copy from a magazine ad, but it’s true). And to have it all sync up so I continue to have access to all that, neatly organized, no matter where I am with whatever platform I have handy when I next want to access those ideas. It really is pretty perfect for a naturally disorganized person like me.
Note links are super handy. Creating hyperlinks between related notes. Especially handy as projects get larger and include many different notes.
For non-work related uses, I like their web browser plugin, where with a push of a button, I can save a webpage (either a simplified version, the whole page as-is, or a screenshot) for later reading. All ending up nicely in an Evernote notebook for that purpose. You never know when you’re going to end up in a place desperate for reading material, and the back of a toothpaste tube is only going to get you so far!
I’m in the middle of doing my family’s genealogy, and while most of my work is done directly on ancestry.com, I’m finding it really handy to have an Evernote notebook devoted to taking random notes. Much easier than using some of ancestry’s note taking features. And again, easier to access when I’m out and about if I need to pull it up.
I haven’t used it very often, but the audio note taking feature has come in handy a few times.
I know perfectly well that Evernote isn’t the only way to do any individual thing I mention here, but having it all organized in one application is pretty damn useful to me. OneNote may very well do all this as well, and may do it just as well or even better, but I like the way Evernote is set up, it works for me, and I’ve been using it for a while so I know how it works well. No Kool-Aid; just a useful tool I find handy.