"It is useful to talk to people I otherwise wouldn't..."
I find the beauty of Facebook is the ability to manage acquaintances and good friends and place them on the same level. However, I also feel that this prevents circles of friends and groups from growing tighter.
"The group and event organization are the most useful features to me..."
They may be the most useful, but there's much more room for improvement.
2. Internet TV - My first thought was, "there is such a thing?" Most of the stations (eg. NBC) block non-US IPs from watching their online programming, so I guess am missing out on that. I almost never watch TV, but there are a few shows I do enjoy, and I would much rather watch them on my own time than when they air. And I would gladly pay a small amount of money to do away with the ads, even if it meant the video file could only be watched once.
3. News.YC is great, partly because it is small.