Is "The Venue in the map" or "...on the map"?

Solution 1:

In the map makes sense if you're talking about a map application on a smart phone. Since this will soon be the way that most people use maps in practice, it will likely become the dominant form.

For the moment, though, on the map is more general, and it also carries the connotation that the Venue is worth mapping, i.e. it will appear on a screen in the app, but also on other wayfinding displays that the user might encounter on their way to its location.

So I'd say that the correct answer depends on the nature of your audience, the importance of your venue, and the impression you are trying to convey.

Solution 2:

A map is a 2-d representation of a 3-d space, in, would refer to "inside" whereas on represents "on-top of", and as there is no inside of a 2-d thing, the correct wording is "on the map"