Update: The change has been made (see rm-rf's comment).
Currently the site description is
Mathematica® Stack Exchange is a question and answer site for users of Wolfram Mathematica.
Wolfram is soon going to launch several products most of which use the same programming language now branded as Wolfram Language. As a result of this rebranding, there already appears to be confusion among people new to Mathematica / Wolfram Language about what the difference between these things is. It is likely that people interested in "Wolfram Language" won't be searching for Mathematica (example).
What Mathematica.SE is mostly about is really the common programming language of all the WRI products.
The launch of these products is imminent (today?).
Therefore it is important that the sit description should explicitly include the words Wolfram Language. I suggest changing it ASAP to
Mathematica® Stack Exchange is a question and answer site for users of Mathematica and the Wolfram Language.
A related question is how to direct traffic looking for Wolfram Language (e.g. SO tag) to this site if/when this search term (tag) becomes popular.