I might be interested, I've thinking about creating my own blog to help gain interest in the products I've been developing. The only thing is I don't use GIMP much which is more accessable to many potential mappers.
I use Xara Xtreme Pro 4.0 - which seems to make me one of its only users for map-making, thus it might be weird to audiences to try and delve in.
As the first deputized member of the River Police, I have some geographic expertise, so discussions on rivers, mountains, tectonic plates, etc could make for some interesting articles. Plus I create lots of maps, so I'm always working on something, and I am also a pro - I get paid commissions all the time, thus I might have some thoughts on helping others do the same.
I'll wait for anyone else interested, before I formally volunteer.
But, the idea is intriguing.