Originally Posted by Wobin

One thing I should mention, is that, while there -are- some altitude mods out there (somewhere) the coordinate system offered by Blizzard is entirely two dimensional, so it does not take height into consideration. So any usage of waypoints etc, cannot calculate altitude. It's also limited by what the API offers in terms of returning locations for targets. Mobs, for example, would not be able to be used, as we have no method for determining their co-ordinates. Flag runners, similarly, -unless- they were your faction (and thus in the raid group), and even then you run into the problem of being in an instance and not being able to get accurate results.

If we could get accurate results for people in instances, it could lead to interesting mods such as "Point me to where the biggest fight is in the BG" and it would search for the largest group of raid members within a certain proximity to one another that were in combat, grab their subzone (eg Blood Elf Tower) and display a waypoint with those details.