Not only social software is popular these days:
Here's an article in the Belgian newspaper De Standaard about social reading in the library: Lezen doe je best in groep (reading is best done in group). Publishers even publish special editions of books for reading groups and group reading.
An interesting project is De leesclub van Mekka (The Mekka reading club), an online reading group and blog, organised and supported by the cultural radio show Mekka on Studio Brussel in cooperation with the newspaper De Standaard.
I found some more online reading groups like the one of British newspaper The Guardian or BookBlog, but they don't have radio support.
Update 12/05/2006: There was a discussion on online social reading in 2004: "Social reading — A niche to be filled?". It poses the question of a website/software where
my friends and I can read stuff together … And we get to comment and annotate for one another.
Update 12/05/2006: The Transliteracies project does research in the Technological, Social, and Cultural Practices of Online Reading. It could be interesting to follow their efforts. They have a "collective reading"/"group reading" topic with until now only 2 small posts that are not even on reading… But they have some interesting articles on other topics.
Another interesting social reading phenomenon is "library dating" (lib-dating, bib-dating, bibdate in dutch), there's an article in today's De Morgen newspaper. The library Tweebronnen in Leuven organizes a library dating activity for the cultural festival Kulturama. Readers meet in a nice atmosphere based on their literature preferences.
is sexier than beer halls.
You have to whisper.
Update 12/05/2006: More promotion for library dating by VCOB (Flemish Center for Public Libraries). They created a bibdate manual and a logo. See also the post on the VVBAD blog: "Bibdate: een sterk concept"