There have been other blips in the past caused by documentation for a project getting moved to a different server and in doing so the SEO for the material (inadvertently) changed.
TIOBE measures the SEO for different programming languages, nothing more.
It has been gamed in the past. For example, http://delphi.org/2008/10/the-many-faces-of-delphi/ and http://delphi.org/2008/10/delphi-keeps-climbing/
There have been other blips in the past caused by documentation for a project getting moved to a different server and in doing so the SEO for the material (inadvertently) changed.
TIOBE measures the SEO for different programming languages, nothing more.