I always thought light bleed was the presence of light when there shouldn't be any. Like when you're watching a movie in portrait view, and the black bars on top and bottom show light. That's why I haven't wasted much time with IPS in the last couple years ever since discovering Samsung's AMOLEDs. Uneven backlighting is a different and even worse artifact, and again it only affects non-AMOLED screens.
Captivate SGH-i896, Galaxy i9000, Galaxy Tab 8.9 SGH-i957, Galaxy Tab 7.7 P6800, Galaxy Note i717, Galaxy Note N7000
Note 2 i317 (AKA the perfect phone) | Nexus 7 | Nexus 10