Who is the target audience?
If I understand correctly, the target audience for the weekly Tech news and
the monthly VE news is experienced active editing Wikipedians (I don't know
if it was ever designated, but I am making an educated guess of the actual
practice).
But what is it for the mobile
Sounds very reasonable. A lot of changes happen in mobile, some are
tangent to desktop experiences, and pro-actively sharing those updates
while in planning or early stage, is a good practice. In addition, keeping
the community updated and aware of what is happening in mobile, helps
present the