As Bryan mentioned here, Canada's complaint about Belgian and Dutch bans on seal products is now official. The consultations request is here.
It might be better for the system if the complaint did not go forward, but if it does there could be some very interesting issues explored. First, there are some classic GATT issues. Canada has made claims under GATT Articles I, III:4, V and XI:1. The issues I would most like to see discussed by a panel are: 1) how Article III:4 applies in the case of a general ban on products; and 2) how Article III:4 relates to Article XI:1 in the context of this kind of ban. And, of course, we could see some novel issues raised under GATT Article XX.
Second, there are some issues under the TBT Agreement that have less history. Here, Canada has made claims under Articles 2.1 and 2.2. Article 2.1 is just MFN and NT together, but Article 2.2 refers to "unnecessary obstacles to international trade" and measures that are "more trade-restrictive than necessary to fulfil a legitimate objective." Part of me really wants to see what a WTO panel will do with these provisions in the context of Article 2.2, but another part is afraid to find out.
ADDED: An astute blog reader pointed out to me that the MFN and NT obligations in TBT 2.1 do not have the equivalent of a GATT Article XX exception, and this could affect the interpretation of 2.1. An excellent point. It could make the 2.1 interpretation as interesting as the 2.2 one.