According to the previews at the end of Episode 165 (subbed by IY4Ever), Ep. 166 is a "Final Episode Special". It's called "The Bond of Two - Use the Shikon Shard!", and it will air in Japan on Mon 9/13 at 7pm. (Expect a subbed version later in the week.) I'm pretty sure this is the last one, folks. =(
Submitted by Mike D.