If you make a multiplayer game and it has chat, please put in flood control or an ignore function. Especially if the chat makes a "ding" sound every time somebody sends a message.
I just met a griefer in Phage Wars Live who liked to spam "la" about 20 times a second. I can't even turn off audio in PWL so I had to mute everything.
By flood control, do you mean that there should be a required wait between messages? If so, Shell Shock Live has flood control, and you can mute users in-game. Also, this is probably something you should mention in a game comment. However, Phage Wars Live is not the only multiplayer game without flood control or a mute option. The same is true for most other multiplayer games (except Shell Shock Live).