Namco, Capcom, and Sega are collaborating with Nintendo on certain Nintendo franchises. Namco and Sega partnered with Nintendo for the Triforce board, which a Namco-developed Star Fox and a Sega-developed F-Zero (both designed by Nintendo EAD) are appearing on. They\'re also appearing on GCN, and being published by Nintendo.
In addition to that, I\'ve read that N\'s licensing fees are extremely competitive. As for MS and Sega, I feel that they have a very close relationship. Closer than Nintendo/Sega. Of course, is Xbox getting MS/Sega-developed games? Not yet, if ever. As for "paying off".. both jointly developed games are coming out in early 2003.. the point where the ball is rolling quite fast according to my estimates. If you want to debate Nintendo, read up.