I started hosting a few projects a libraries on github, My repo. is located at https://github.com/tuxbotix.
In the recent years, GitHub has become the de-facto place to host open source projects. The success has been proven by the number of Sourceforge projects being moved to Github and the closure of google code (and their suggestion to move for github).
Git has been there for a long time, in fact it was there since the days linux kernel was born and git was invented by Linus Torvolds and he used git to manage the source of linux kernel.
However I believe that ease of use and the clean interface of github made many people to use it rather than sourceforge. I have a sourceforge account too, but I almost never used it and even to date, browsing through the source, downloading, etc is somewhat inconvenient and there were instances that the advertisements mislead people!.