I strongly support keeping the MUG mailing list. It would be a great loss its disappearance. I, too, collect suitable MUG messages in a searchable local file that serves as my first source of info where on-screen help fails. I would not want to give up this concentrated manual for any diluted news-group. My vote is for retaining the existing mailing list.
Procedural details are below.
It was started in 1981 as a research project at the University of Waterloo and has evolved in one of the leading tools for computer mathematics today. In some cases the discussions are very specific to specific software products. This is fine for the latter groups which were set up specifically for such discussions. However, it is not intended for such groups as sci.math.symbolic which was originally intended for discussion of issues that primarily deal with the mathematical algorithms for symbolic computing along with other mathematical and computational issues related to computer algebra systems. Unfortunately discussions dealing with only Maple related issues are now a common occurence of this newsgroup.