Annoying Expose
Now every time you click-hold or option click-hold, it triggers Expose and the pop-up menu is not directly above the icon. It is horizontally across. So if you want to quit or force quit, you have to move the mouse off to the side to select the quit/force quit option.
It was more convenient before if you had no interest in Expose. Now it is kind of forced on you with no way to go back to the previous method.
iMac (Early 2008) Intel 24" 2.8 GHz, PowerBook G4 15" Titanium 867 MHz, Mac OS X (10.6), iMac G5 (iSight) 20" 2.1 GHz, Power Mac LC 575, PowerBook 540c, Duo 230, 2300c