It seems that some high quality fast prime lenses (50mm f/1.2, 50mm f/1.4 - there is also an 45mm f/1.6 and a 60mm f/1.8) are in the pipeline at Canon. I am not sure though (from translation) that they are EF lenses. See at
http://translate.google.com/translate?sl=ja&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&eotf=1&u=http%3A%2F%2Fegami.blog.so-net.ne.jp%2F2013-03-29
The original source: http://egami.blog.so-net.ne.jp/2013-03-29
http://translate.google.com/translate?sl=ja&tl=en&js=n&prev=_t&hl=en&ie=UTF-8&eotf=1&u=http%3A%2F%2Fegami.blog.so-net.ne.jp%2F2013-03-29
The original source: http://egami.blog.so-net.ne.jp/2013-03-29