Afflalo has some definite NBA strengths, probably most notable is his help and individual defense and the never-lose sort of mentality he puts into this aspect of the game. His shooting is a plus but there are many shooters in the NBA level, and that is just an addition to his game and not a real plus as he is by no means a super shooter, rather more of a scorer. His passing ability is rather ordinary although with Farmar running the show and with him investing energy on scoring and defending, it's hard to gauge this aspect of his game.
There's really no knock to his game, no truly severe weaknesses, besides his physical attributes, which immediately puts him below many of the NBA prototypes waiting to be drafted; Afflalo is a 6'5" wing player, which is very mediocre size. He also doesn't have the athleticism to make up for it, which is rather ordinary at best. His footspeed is all right but he is more of a half-court set player rather than a transition player. Athleticism is a huge factor between who gets drafted higher and who gets drafted lower in terms of the NBA, and in order to make up for average athleticism, a good skill set is needed to be drafted high. Afflalo has a decent but not good skill set, more reason why he should stay another year at UCLA. JJ Redick has shooting to make up for his lack of athleticism; to make up for his height, Maurice Ager has uber-athleticism. Afflalo doesn't have either as of yet, but he can certainly develop it. There's no rush--he's a sophomore.
However, Afflalo has gained exposure by burning his draft card this year, learning that he's most likely an early to mid 2nd rounder at this stage. He could improve on that once he improves his skill set, notably his passing and all-around ability.