Internet growth has been an interesting thing to watch, especially if you have been online since the mid 1990s. In the past two years it has been especially quick, exponentially growing each year. In 2006, an estimated 27.4 Million sites were added to the net, making the total number of available sites over 100 million. The study, done by Netcraft, also includes some interesting polls on what software is powering those sites. In 1995, the NCSA web server and CERN made up the large majority, with Apache being merely a fraction at 3.5%. Today, Apache dominates all others with over 60%, and Microsoft's IIS (which didn't even exist in 1995) is second at 31%.
Fascinating stuff. With that rate of growth, we'll perhaps see 150 million or more by the end of next year.