My 2007 odyssey, 69,000 miles is making an intermittent scraping sound while accelerating. It is soft and sounds a little like a snow shovel being used.

 

Check out your heat shields on the exhaust.

 

Might also be a wear indicator on the brakes just starting to hit.

 

Totally agree. I crawled under my Odyssey and found that the aluminum heat shield had wiggled enough to break free from the retainer screw and was scraping and flapping against the catalytic converter. I simply put a nice wide fender washer over the break and re-secured it.