Actually what we have here in the U.S. is Bison as opposed to Buffalo. They are of the same family but Bison is native to North America and South America. Buffalo are native to Asia and Africa (Ie: Cape Buffalo, Water Buffalo). I gleaned this knowledge several months ago when I posted about a "Buffalo" feast I'd done for some of my friends. I'ts become a very common misnomer and many people make the mistake, including the companies who raise, process, and sell the meat. The primary noticeable differences are that the American Bison has the beard, the big hump on it's back, and is able to withstand extremely cold temperatures.
Having shared some knowledge gained from SMF, now to your question: Yes, I have made sausage with Bison meat and it was outstanding. I had 2# of Bison sirloin steaks left over from the cookout. I used those, about 3/4# of homemade pepper crusted bacon, and 1/4# of Brisket fat that I'd saved. Used a somewhat traditional Texas spice mix that I'd come up with and added some high temp cheddar cheese. Absolutely one of the best sausages I've ever made. Very deep color, rich flavor, and a texture that makes you just want more and more. Matter of fact, one of the guests at the Bison feast was OK with the meat but not overwhelmed with it. The sausage however she proclaimed was the best I've ever made.....and I've made a bunch of different ones. Do not hesitate to try it but make certain that you have the proper fat content as the meat tends to be very lean.
Hoping to help a bit,
Robert