One context per task is plenty in my opinion. If you need more then tags are a great alternative.

I would like to assign multiple contexts to a task. I use contexts for the different weekly meetings I attend, and I create tasks for ad hoc agenda items. When I'm in the meeting, I click on the context to lookup agenda items for that meeting. But I often run out of time and an agenda items must wait for the next meeting. When I create an agenda item, I would like to pick the multiple meetings in case I don't get to it in the first meeting.

Contexts should indicate a person, place or tool that's *required* to complete the task. If you can do it at home or work then neither of those is really a "context" for that particular task. I suspect, though, that there is something that's required to be able to do it - e.g., a PC, internet connection, telephone, etc. I agree with dd: if you need multiples, use tags instead - that's their purpose!

Contexts are more appropriate to the GTD method e.g @home, @work. Therefore allowing selection of multiple contexts would be useful.

I think the idea of contexts is that there is always one context. And I think this is good. If you need multiple contexts you can use tags instead.