IMO, JKD incorporates not only techniques of different systems, but more importantly, concepts and ideas. MMA pretty much seems to just grab techniques that may work in the ring.
"JKD", "MMA", they are just names but they are NOT one and the same. If you practice JKD, you should enter a MMA event and see for yourself what works and what doesn't. You can still call what you train whatever you like.
No, I dont think they are the same! Comparing the two would be like comparing judo and jiu jitsu are they the same? Yes, they share some similar philosophy, or concepts, But they are not the same.