I've wondered about the same thing. Heck, somebody could fork Bookwyrm and adapt the book-centric features to film and TV production and release terms.
It'd be interesting to see this with many things, movies, records, and comics come to mind but I'm sure there's more.
I could swear I found some federated wiki or similar that catalogued all sorts of objects and media, but it completely eludes me now. That could be a back end for more specialised projects.
Edit: Apologies, I was thinking of Inventaire|github. "A libre collaborative resource mapper powered by open-knowledge, starting with books" — so the project is open to other media but focuses on books for now.
What about reviews for other things like businesses?
Free and Open Source Software
If it's free and open source and it's also software, it can be discussed here. Subcommunity of Technology.
This community's icon was made by Aaron Schneider, under the CC-BY-NC-SA 4.0 license.