Obviously this is in large part due to the fact that you're not competing with everyone for the same kills. When I did the Ned, Lord of Rhinos quest the first time it was a chaotic melee as something like twelve groups (groups, as in two or three people per) vied to tag the guy as soon as he spawned. And even as parties would get their kill and move on, more would keep arriving so that some people waited for upwards of an hour while those that have the better instant casts tended to get the tag off. When I did the quest on my shaman a couple of weeks ago, it was much more managable, I basically just waited until the horde party tagged him and got him on the respawn. And when I did it on my night elf last night, I basically had Ned all to myself. Borean Tundra and Howling Fjord are effectively deserted compared to their state after the launch.