Full details on SC2 Patch 1.4.3 at
http://us.battle.net/sc2/en/blog/4487503/Patch_143_Now_Live-2_21_2012#blog
I don't think Protoss needed the
Buff to Phoenix, but this is will make Phoenix harass of mineral lines a LOT stronger.
I don't know if this buff will matter much for Protoss vs Zerg, but it can make a big differencefor Protoss vs Terran!
Though I am not sure anyone will use it for that, cause you can't get it early, but this will really
strengthen Protoss Air vs Terran Air, since only real counter Terran has to Carriers is Vikings, and this will make it easier for Phoenix to neutralize Viking threat to Carriers.
May helps
defend vs Terran 1-1-1 builds as well, since
Phoenix will out range Marines now!
Phoenix are tough, even pre buff they coul harass mineral lines even vs 2-3 Turrets, since they have enough shields to last while they 3 shot SCV's with their bonus to light damage.
The range upgrade will let them position even better, since they will have range 6 attack vs Range 7 of Turrets.
This may also lead to Terran getting autosec tracking upgrade to get the +1 Range upgrade to Turrets, as well as PF.
Another very nice thing about this upgrade is that with this upgrade Phoenix will have same range as Voidrays!!!!
Which means Phoenix + Voidrays will work much better together, since Phoenix get bonus damage to light and Voidrays get bonus damage to Armored.