Wow! That was fun! I really like LibraryThing. I sat down in front of my bookcases, set up an account and added 25 books. Some of them are history books I've read for classes I currently teach or have taught in the past. I added all of my John Wayne books (but one that must be in a box I haven't unpacked yet). I put a few books I learned about/found while living overseas.
I looked at some of the features of LibraryThing. When I clicked on "groups", I found a group called History: on learning from and writing history. I read some of their posts. It was really interesting because there was a series of posts discussing the issue of how/why groups of people get their own countries, such as Jews, but others do not, such as Kurds or Palestinians. One of the posts discussed Wilson's 14 Points and the countries set up at the end of WW I. The person mentioned reading Paris 1919. I had just come across that book when doing Thing #7 and using Google Advanced Search.
This could be really useful. Reading ideas about historical topics and finding books others have read and their comments about them would also be useful. I spend time in used book stores looking for books to put on my shelves for my students to read. Being able to read reveiws and comments about books would help me know whether a book would be interesting or as useful as I hope for my students.