Congratulations for creating my favourite corner of the internet.
It's all good, and the most fun/useful section for me has varied over the years. When I first joined it was the device-specific groups for those early eInk devices, then I discovered Calibre, and more recently there's a lot of time spent here discussing tablets - but that's all good too.
I've also got a lot out of the politics/religion group (and the various threads that eventually led to the creation of the group). There have been some seriously thoughtful threads in there, not to mention some very lively ones, and much of the time this has led to exploring references outside MR.
Favourite thread? Ah, I think we need to get back to the haikus