I don't know if you guys already knew about these 2 very useful library to drive servo motors from the arduino, basicly you don't need to use analog write with an hexadecimal value to drvie the servo by PWM, you just write in degrees the angle and direction you wish the servo to go and it goes!
Anyway here it is :
http://www.arduino.cc/playground/ComponentLib/Servotimer1
"This library controls the servos completely in hardware. You should expect less than one clock cycle of jitter and to never see an extended, delayed, or missing pulse. It also will not disturb any of your program's other timing." - from theservo timer1 page.
There's also this one that uses software to run up to 8 servos, still using degrees instead of analog write :
http://www.arduino.cc/playground/ComponentLib/Servo
I still have to try them, but they look like it'd make controling a servo via arduino a lot easier.