Yes, and mostly love it. Just not happy with the structure of my information management strategies, at least for daily work documentation. Put "X" under the specific project I'm doing it for? Or what if the learning seems more general... should i start a new tree for longer-term reference knowledge? Or summarize the specific knowledge more generally and keep a copy of both in separate areas? Or write only one and link to it in the other?

Stuff like that.

Other benefits I've really appreciated:

• embedded/executable code blocks. This is my favorite, favorite feature, and I will never go back (if I can help it) to running analysis code (I do a lot of data analysis/viz with R/ggplot2), generating plots, and then having to insert them into a .doc or .ppt.
• on that note, being able to export in general is a fantastic feature of Org. HTML, PDF, markdown, whatever. I love not having to futz with image placement manually. Get something you like with some #+attr_html/latex arguments, and then insert a bunch of images really easily by just linking to their location on disk.
• org is the only, or one of the only, applications that lets you mix and match notes and todos. I used to use TiddlyWiki for all of my work notes and really liked it. But I had to manage todos in something else. But why? Todos often come about in the context of notes, say in a meeting, or for some home project. I really like being able to keep the todos in Org right with whatever prompted the need for action (then view just the actions you need to complete with agenda views).
• Clocking/time tracking is another aspect that seems awesome, but I haven't started using. I'd love to get to the point where I record what I work on, and especially an estimate + logged hours. Not sure what I'd do with the data, but having it vs. not at least makes post-analysis a possibility.

Still, my various attempts at org file structure seem to end up cluttered and with things structured really oddly. I'll kick off a project with my estimate of what "categories or knowledge" it will require, and as the months or years go on, I'll be in a rush and just resort to keeping a date tree and stuffing the stuff in there like a journal instead. Now I have project-specific info scattered around through monthly journal trees. Harder to archive/find, and end up unfolding a bunch of headlines to find stuff.

Anyway, neat to find other users, so I thought I'd comment even though I'm really late to do so!