I'm not sure if they are technically "owned" by ford in a corporate way, but the two companies share many unibodies and powerplants.
The rotary engine is an amazing feat of engineering, as far as power/weight ratios go. The mazda rotary series of vehicles (RX, essentially) and their turbo performance versions have always touted the best center of gravity, often low and 50//50, and a powerful power/weight ratio... this leads to nimble, quick performance - something almost difinitive of the 'tuner' ideal.
Comparing an equally performing 90's rx-7 to, say, a 350z... I'd rather be driving the RX-7. Not to mention the cars are gorgeous.
I wasn't AS fond of the RX-8's as I was of the 7's, but the 9's seem quite nice. I still think they'll be too mainstream to carry on the finesse of the 90's RX series.
Something about the ~90's and their imports. Supras, RX-7, Skylines, yummmm.
Edit: In regards to the Wankel engine it's also capable of compressing volumes of air better than other engines, because of the way the valves/injectors function and the overall volume of the chamber. When you start looking at the high-pressure direct injection technologies that are surfacing I could imagine Wankels taking giant strides in the next several years.