The title says it all in this poll tell us what your favouite social networking site is my favouite currently is facebook but Google plus looks promising so maybe Google when it comes out of beta mode
Facebook since I can easily find groups, pages, and friends pages with a lot of activity on it, so there is always something to read, videos to watch, and photos to view.
I also use Facebook quite often to promote my blog posts which get me a few readers per month.
Plus, some of the flash games are a great way to stay entertained when I have nothing to do.