You may have missed the memo on what a meme is but this site does a great job showing what is popular and how to gauge it. It also is an interesting window into internet search and what is relevant. Here is a perfect post that shows how they look at traffic and search to see where there is growth and what is there Facebook, is it sustainable? Read it and it will start to make sense.
Another good post to illustrate the concept is this one regarding recessions. He shows how search and interest in a topic can be an indicator of the likely hood of that event happening or being successful.
If you study the writings on RealMeme.com you will come away smarter about uses for the internet. If you are like a lot of visitors to this site you probably have a blog and if you want to quantify any of what you do then studying Meme’s can help you target current relevant material for your readers.