Show last commenter in forums summaries

Rather than display the author of a topic on summary and in the "recent discussions" list, display last commenter.

In my group, but I think it might apply to more cases, I post the most, so it looks as if I am the only one active, while at the same time many people respond to discussions. If you display the last commenter it shows that the group as a whole is more active and that is excellent for group building, I think.

If people want the original author, maybe you can create a toggle between author/commenter.