This is actually my favorite GUNSMOKE opening, rather than the more famous showdown(s). By this time in the series, the characters are not only old friends with each other, they're old friends of ours as well. This opening just seems very heartwarming to me.
Also, Jim Meals has contributed an excellent piece about the GUNSMOKE radio series over on the Western Fictioneers blog. I highly recommend that you check it out.