Supported Devices:

PowerBook:
PowerBook G4 (Titanium) Late 2002
PowerBook G4 (Aluminium) Early 2003 or later

iBook:
iBook G4 Late 2003/Early 2004 or later

MacBook Pro:
MacBook Pro (Aluminium) Early 2006 or later
MacBook Pro (Unibody) Late 2008 or later 

MacBook:
MacBook (Polycarbonate) Mid 2006 or later
MacBook (Aluminium Unibody) Late 2008

MacBook Air:
MacBook Air (Aluminium Unibody) Early 2008 or later

PowerMac:
PowerMac G4 (Quicksilver) Mid 2001 or later
PowerMac G4 (Mirror Drive Door) Mid 2002 or later
PowerMac G5 Mid 2003 or later

eMac:
eMac Mid 2003 or later

iMac:
iMac G4 Early 2003/Late 2003 or later
iMac G5 Mid 2004 or later
iMac (Intel) Early 2006 or later
iMac (Aluminium) Mid 2007 or later

Mac Mini:
Mac Mini G4 Early 2005 or later
Mac Mini (Intel) Early 2006 or later

Mac Pro:
Mac Pro (Cheese Grater) Mid 2006 or later

Initial Release: 10.5.0 (October 26 2007)
Latest Release: 10.5.8 (August 13 2009)

New Features:
- Cover flow
- Skeumorphism
- Last MacOS version to run on PowerPC
- Boot Camp
- Spaces
- Time Machine