The DFB post dates back to when they were still handling reservations in-house. I did the wine tasting in Oct, and they mentioned that going forward it would be handled through the normal ADR system.
I haven't been able to find it online, but you can book it now through WDW-DINE. It might be grouped as a dining event since it's prepay, not CC hold. When I checked a few weeks ago, it was $31.25 pp.