Ringneck:
The HRR216VYA, like many Honda models, has running changes now and then. Honda indicates these with a sometimes hard-to-find code in the full model name. These are called "K-changes." You can see the full model name on the data plate on the back edge of the mower deck, or on a paper label on the outside of the carton.
HRR216
8VYA was built up until January of 2012. Many dealers are discounting them to make way for the new versions.
The new HRR216
9VYA is new for 2013.
Changes between the K8 and K9:
-K9 adds the Clip Director, which allows for instant change between mulch or bag/discharge. No loose parts, no mulching plug.
-K9 has an improved twin-blade configuration called MicroCut, that provide better cut quality.
-K9 has a slightly different styled fan cover.

-K9 has improved design under the deck (scroll, belt cover, ramp, etc.) for better mulching performance.
Lots of details about the HRR216VYA at Honda's website:
Honda Lawn Mowers: HRR216VYA