They buffed BLU's spells due to off-guard/peculiar light both being turned into Trick Attack-like effects that only apply a weak 5% debuff that can't be stacked due to the shared cooldowns (They used to boost damage by 50%/30% respectively).

BLU will have no issues with target swapping now and their single target DPS is apparently higher overall now. AoE DPS went down a bit, though.