So if Mr. Most-Complete-Astronomy-Software-Available reponded to a
reader's question about astronomy software, I say it's fair use.

The issue of new product announcements has been discussed here before. If my
memory serves me correctly, I believe a consensus was reached that a one time
product announcement is acceptable if it is tame and if the information that it
is a commercial is included in the header.

Good examples of properly done announcements are Brian Tung's.

I personally think this announcement was a bit aggressive but still, there are
people who do use this software.

I am curious if you have read the S.A.A. charter in this regard? It is pretty
silent and I think leaves the decision up to the group.

My vote is one time product announcements by small vendors, especially those
that are members of this group are fine.

jon