>Mean Look prevents the target from switching out. The target can still switch out if it is holding Shed Shell or uses Baton Pass, U-turn, or Volt Switch. If the target leaves the field using Baton Pass, the replacement will remain trapped. The effect ends if the user leaves the field or if the user or target faints. Note that if the user then uses Baton Pass, the effect will now end. Pokemon protected by Magic Coat or the ability Magic Bounce are unaffected and instead redirect this move back to the user. Does not prevent the effect of Eject Button. If the target is hit with Roar or Whirlwind while Mean Look is in effect, they will be forced out as per normal.
In addition to this Mean Look does not work on Ghost type Pokémon and Dragon Tail and Circle Throw will also force the affected Pokémon to switch out.
A Pokémon with Run Away or holding a Smoke Ball can also escape from Mean Look in wild Pokémon battles. Run Away and the Smoke Ball do not work in trainer battles.
>If a wild Pokémon uses Mean Look on the player's Pokémon, the player will be unable to escape, unless the player's Pokémon has Run Away or is holding a Smoke Ball.
Source: http://www.smogon.com/bw/moves/mean_look
http://bulbapedia.bulbagarden.net/wiki/Mean_Look_(move)
Hope I helped :)
