Chats and Forums

Casual Players Alliance
Magic articles for casual players, a message board, chat, and online polls.
http://www.casualplayers.org/

Chase MTG
Includes a java-based chat room for discussion of the tame.
http://chasemtg.tripod.com/

Deckmaster
Discussion board including news, strategies, deck ideas, and selling of cards.
http://p208.ezboard.com/bdeckmaster

Gamers' Central
Offers a general discussion and interactive deck forums.
http://p220.ezboard.com/bmagicthegathering44965