Thanks. I think I actualy found something in the Player's Handbook. (i forget the page number, but it is near the beginning when it describes new background info)
It refers the player to the monsters book for creature abilities.
My interpretation is as follows, but I'd like to hear other's thoughts on the matter.
I think the beast skin ability should be a double edged sword. While in animal form, the character basically has the motor function of an animal, while maintaining their normal mental capacity.
This effectively means that they can't use weapons or any other abilities that require fine motor coordination such as: craft, sleight, lockpicking, etc.
I think this should be offset by temporary skill increases while in animal form.
Here are some ideas off the top of my head.
Wolf Form: -20 to athletics while climbing, + 20 to tracking, + 10 to athletics (except climbing), + 10 to perception
Lion/Cougar Form: + 10 to athletics when jumping or climbing, +10 to stealth, Night sight
Bear Form: + 10 to perception, + 10 to tracking, + 10 to athletics
Bat Form: Gain flight skill, Bat sence (dark sight essentially), + 10 to perception
Thanks in advance for your help.