The how and why of ultrapeer connection are quite secondary to me, as is total accuracy. All I can tell you is that the number of search hits is inversely (and geometrically) proportional to the number of ultrapeer connections which use MorpheusOS and Gnucleus. I would say that if half my ultrapeer connections are these two, my search results can drop to as little as a tenth of what they are with Limewire ultrapeers.

This easily occurs, since they hold the connection so much better than a Limewire host.

A Morpheus ultrapeer used to be fairly rare. Why are they so numerous all of a sudden?