How did you come to this new conclusion, did I miss any article? All available statistics and articles [1] [2] point to the fact: most users on Gnutella are freeloaders.

Supernodes will not integrate modem users. Supernodes will together with search-caches: reduce backbone traffic + improve network topology + increase horizon (more available files).

I expect much more positive effects from swarming. I allready posted swarming ideas here, a short summary from that:
The bandwith of modem users is completely wasted right now and modem users are often "forced" to be freeloader. Actually this egoizm is contraproductive and means less files for all. While high bandwith users can share the traditional way, swarming is a key to make low bandwith users share with the network, without any significant negative effect or traffic-overhead. Swarming will: make low bandwith user become a valueable resource + spread often requested files + balance load + less "busy" servants (more available files + higher bandwith).

Greets, Moak