CompuServe Messages

I have had this happen exactly once on each of my machines. Interestingly enough, it was on the same day. MWB was installed on each machine on 2 different days. I wonder what algorithm he is using to decide when and/or how often to pop up his surprise? It hasn't caused any problems; it did its thing, then the boot proceeded normally. I wonder if we get it only once per machine, or does it reoccur every so often?