I dont think so
Once i went in to a cave and experimented. There were no mobs at all! I could only find one lame zombie! I think they should spread the spawning of monsters more evenly!

Lately when i have been playing i realized that the mobs are really weak and does not provide enough of a challenge. The gawme minecraft has to main aspects, survival and building. Without one aspect we lose interest in building a super tough fortress or making diamond swords. It pointless. Because of this some of my friends have stopped playing and lost interest. It would be greatly appreciated if you could somehow buff them or make them provide a challenge. 

Thanks, ScholarSun