A) As mentioned before, 3D engines usually support more units on the map than 2D engines.
B) ES programmers are working on making m-player games more officient and less laggy.
C) 16 players games will be excellent for LAN parties, where bandwidth isn't a problem.
D) AoM will be released in 8 months, and it will probably be played in even in 2-3 years, when many of the players will have computers/connection that will support 16 players game.
E) 16 players = endless diplomatic options for single player scenarios .F) About the colors: I guess the colors won't be distinguishable like 3 players game's "red-blue-yellow", but it isn't hard to find 16 colors (what was discussed here many times).
G) I believe 16 players games won't be so common, just because it's hard to find 16 players on the Zone who want the same conditions. But as mentioned before, it'll be nice on forum parties, etc.
And of-course, if you think your computer/connection can't handle 16 players, no-one makes you play a 16 players game . (my 350MHz CPU won't handle 16 players for sure )
The Last Knight
Grasshoppers are cheap, nutritious, tasety,Kosher and easy to dissect