I want to know if Buffalo will release a new firmware update with newer dynamic dns services (afraid.org seems to be the best positioned because it's community driven, or others [1]), or if we need to upgrade to DD-WRT firm to get it working another time.
Also I would like to know the answer to your question.
I just bought a WZR-600DHP2, and I am really happy with the product; pity that without a DDNS becomes difficult to use the built-in PPTP service (the main reason why I chose Buffalo).
The DDWRT firmware gives multiple options for DDNS.
Not all Buffalo's products can install DD-WTR (or at least not yet, mine is not in the DB).
So would be the case that Buffalo found a solution to the problem, integrate no-ip, zoneedit or another free service for you to use at least the integrated vpn and other services of the device for which it is necessary to use a ddns.