Based on some VOO subscribers (and special thanks to Patrick Vande Walle), it seems that VOO (the cable operator) is the 2nd residential ISP (after EDPnet) and probably the largest Belgian ISP to deploy IPv6.
As written by Patrick:
Several VOO customers have reported that, after a firmware upgrade of their CPE yesterday, they started to receive a /64 IPv6 allocation.
This seems currently limited to the customers with a Docsis 3.0 – compatible modem (the Netgear ones).
There is no official announcement yet, but a press article
There is also a forum discussion
The IPv6 Council is sure that EDPnet and VOO will not be the only IPv6 residential ISP in Belgium! Let’s the fun begin 🙂