Somewhat out of order...
I think that sports like mixed martial arts apply a pressure to traditional systems to re-evaluate themselves. I do not think this is a bad thing. I think the success or failure of MMA as a sport is largely irrelevant to traditional systems, as they are apple and oranges. I think aikido has a great opportunity to evaluate themselves and I hope we take advantage of it. I hope our MMA friends take the opportunity to share what they are learning on the mat, after all they are training with an intensity that we rarely experience in our regular training.
Now, some of that "learning" is painful. As part of our evaluative process, we are getting a great look at the floor as our training falls apart in some respects and MMA guys training for 6 months are eating aikido people alive. We are also getting a great look at our presumption that aiki is some mystical force exclusive to aikido. Finally, our confidence is being shaken as we see better [sport] fighters in shorter training periods who are not choosing traditional training. Throw in a rising minority of aikido outlyers who are training through a different paradigm and rising to meet this challenge and aikido has some couch issues.
Aiki is a great tool, learn from where you find it.
I dunno. If MMA puts any pressure on traditional martial arts, it is on practitioners, not on systems.
Most of the usual "MMA vs Aikido" stuff seems to fit here. In what venue are MMA people who have trained for 6 months "eating Aikido people alive?" The ring? Give the Aikido people 6 months of training and see what happens, right? Are the MMA people stepping onto the mat to learn Aikido, either traditional kihon or internal strength principles?