In nature, often, but not always, if something doesn't evolve, it eventually becomes extinct.
I think that aikido can and should continually evolve to meet the needs of its practitioners and society.
I think the fear that some have today is that aikido is devolving. There are a host of reasons for this perception that have been discussed at length on other threads and forums. It seems that Aiki Expo is attempting to address this situation this year.
Ultimately, the final responsibility falls on the individual student. Will he continue to sit around in his small town and lament the fact that there are no high-ranking teachers nearby to spoon-feed him aikido, or will he get off his selfish butt and go seek a high-ranking teacher and then train diligently for a number of years in an effort to achieve a basic understanding of his art?
Life could very well pass you by if you wait for a shihan to come to your town and teach you on a long-term basis.
Traditionally, the student seeks out a teacher — not the other way around.
In the end, it's aikido students that need to evolve — not the art.