Some say VOIP causes extreme lag in certain cases.

That's true. Mygo's servers lag a lot recently hopefully tmnuts will do something about it.

I prefer to play on EA TH (thailand) servers. They have the best ping. Next up is probably OGN servers over at Australia (stats seem to update pretty quickly).

On another note, I feel that Battlefield 2 engine cannot really cope with 64 players. A 32 player server responds much, much better. If you're on the ground with like 20+ players in a battle, melee fights almost always guarantee jerkiness and death.

In the Commander view (press Caps Lock), you can see a list of squad on the left pane. Select a squad (or use CTRL to select multiple squads) and then right-click on the map to bring up a list of orders you can give.