I'm working on getting my personal library into LibraryThing (always slow going, mostly because I'm fairly specific about my tagging), but really love the interface and potential linkage between different kinds of use.
I'm also using it for a library organisation project for a friend, where it's extremely useful. She's a writer, working on a project in a particular time period: I can tag all the reference books she has for that topic with a specific tag that means she can find them easily. More than that, one of the reasons I recommended LibraryThing is that she can check if she has a particular book when she's out and about if she needs to, which was a really important factor for her.
We've been doing a lot of talking about diversity and privilege issues at work this year. In one of our conversations about what our current patterns and methods do, my boss and I were explaining some of the issues with Dewey, and the fact that it's an artifact of the times.
We've talked about putting our fiction collection (relatively small: about 1000 books) into LibraryThing, so that we could then tag things in new and interesting ways - make connections between books that aren't always obvious in our current catalog - for example, highlighting cultures, types of protagonists, etc. (And more to the point, we could encourage other tagging, easily adapt it, etc.) It would also make a great launch point for pleasure reading lists (something we try to do before summer break).
I also find LibraryThing's blog very interesting for an insight into not only what they're doing, but how it fits into other online book-related projects.
As I mentioned, we're currently doing our lists and other info on our Moodle site, because our students are already looking at other Moodle sites (for classwork and other information), and we've found more of them look if it's on Moodle rather than elsewhere. Interconnection, however, might be a really interesting process, and worth doing. (i.e. as we put a booklist together, insert a link in Moodle, and so forth.)
Sharing what I read:
One thing I've struggled with is being public about what I read. My personal library collection includes some books that are old favorites, but aren't as much a reflection of my current tastes as of fond nostalgic memories. I have a number of books related to my religious practice - but some of those are books I disagree with, but keep around so that when they come up in discussion, I can be specific (with page numbers) about my concerns or disagreements. And I have a certain amount of mind-candy pleasure reading that isn't most of what I read - but is a lot of what I want to read at short notice when I'm tired or grumpy. (which is why I hold onto it, rather than getting it from the library)
Because of all of this, I feel weird about having public access to my library generally available (or even about listing *everything* I own or read anywhere online: without some additional context, I strongly suspect people would get an incomplete idea. For that reason, my personal LibraryThing is set private: other people can't see it.
I do use GoodReads to track some of my reading (I'm trying for more, but it's more because I forget to enter things than because I feel weird about entering it - explicitly because my review and commentary shows up directly with the book when it's associated with me, so people can see it really quickly.
I freely admit this is a weird quirk, but it does affect how I enter books for personal use, and talk about them.