[Brian]

As Kourosh mentioned, the advantage of the "Waiting For..." approach is that you have one list which contains all your delegated tasks.

What works best for me is to leave the actions assigned to the context of the person I'm waiting on, and then use the start date field to hide those actions until some point down the line when I want to check back with them. Whenever I'm in a conversation with them, I can just bring up their context and run through whatever items I have open.

A side benefit is not needing to move stuff from one context to another and then back again during your reviews. (At the cost of having that list that Kourosh's method gives him, of course.)