Maybe a bit better replay:
O.k. Firstly this isn't strictly PvP only. It works against zerg too (bit more tricky).
P+P = Phoenix + Photon Cannon
VR = Void ray
The opening: Standard till core, early gas is helpful. Get a forge depending on what your opponent is doing (if he's teching, you don't need it so early). Place your gateway / forge / core on your choke to create almost a complete wall in. If early pressure starts to hit you, block it off completely with at least a pylon.
Early game: Get a stargate, pump CB phoenixes constantly. Use phoenix to scout and give you info on how many cannons you need (obviously you don't need that many if he isn't massing up very fast). Grab your natural expo, get cannons infront of it, use your phoenix for probe / unit harassment, don't over comit. Place down 2/3/4 more stargates when your gas starts to mount up.
The end game: Once your expansion is up and running and you've taken both gas, start pumping straight void rays. If you are attacked (before void rays come), your phoenix and cannons will deal with everything. Grav beam any enemy units when they are in range of your cannons. Just... grav them all, no need to rely on the phoenix shooting them, the cannons will rip through most armies. Chain grav until you have no energy of the army is dead. Attack when you have 2-4+ void rays and several phoenix. When you engage, lift as many ground units as you can. This prevents a focus fire of your void rays and gives them time to fully charge up.
Protoss has 4 valid anti air units: 1) Stalker, 2) Sentry, 3) Phoenix, 4) Void Ray. Yes there are others but they aren't readily available in mass numbers.
Phoenix are quite cheap, so are cannons. For roughly every phoenix + cannon you produce, your enemy can produce 2 stalkers (300m + 100g vs 250m + 100g). Each phoenix can disable 1 stalker, and a stalker can not win a 1v1 against a photon cannon.
This gives you a solid defence setup. It also gives you superior scouting and you can get a harass in against their probes. Even if they have a couple of stalkers in their mineral line, a group of 5 phoenix can move in, get a probe kill and get out before the sheilds are even broken on a single phoenix.
If your enemy hasn't gone stargate first, you will _always_ have air superiority since you are producing only from your stargate. The solid defence then allows you to then transition to void rays once you have your natural expo up.
The reason why you go phoenix instead of void ray first, is because void rays are easily focussed by stalkers before they are charged, and in the early game, void rays are simply too expensive. A player that goes straight stalker will beat a player who goes straight void ray.
Phoenix also can take down void rays very easily, providing they are not allready in your base and fully charged. You need to play very aggresively with your phoenix, making sure you always know what your opponent is doing, and where their units are.
The combination of Phoenix and void rays destroys any combination of equivilent value protoss units, except maybe straight void rays, but you will gain a superior amount of phoenix and you can fly into their base and keep the VR numbers down.
If you see an immortal has been produced, halt your phoenix production and get a void ray. While the immortal can be lifted, they deal rediculous damage to cannons and take a long time to die to just phoenix + cannons. You need some help from a VR ;p
There are only a couple of counter I can see for this build. One would be a combination of stalkers and high templar using feedback. Of course this isn't very straight forward. Firstly, you can remove all but 50 energy from your phoenix before a fight by picking up your own units. This would mean 50 damage from a high templar which cost them 150 gas... which is obviously very innefficient. If you didn't remove your energy from your phoenix, a few high templar could instakill all of your phoenix with a 200 damage feedback and you would lose the fight, so while I'm listing this as a counter, it's still a very shakey one.
The other two main counters are either an early drop (which can often be scouted by roaming phoenixes), or an early blink + obs jump into your main. The obvious solution to this is to either scout the twilight counsil and start producing more void rays. Or simply add more cannons around the perimeter of your base to try and prevent the observer from getting a look up your cliff face.
An ambitious counter would be hallucination of stalkers, + mass stalkers. This would suddenly give your enemy a much larger number of stalkers available to focus fire down the void rays. Some of the fake stalkers would be picked up by the phoenix but many more real ones would remain. Luckily, hallucination isn't exactly a standard setup.
DT's - Covered (cannons)
Fast zealots - Covered (forge + wall)
Robo push - Covered (lifting more units than they can produce)
Collosus - Covered (Void rays + phoenix)
High Templar - inneffective
Voir ray rush - Covered, Phoenix will win
Mass stalkers - Covered in defence and then overpowered with VRs.
Let me know what you think. I haven't tried it for too many games, but it hasn't lost one yet. The concept to me feels like it should be a standard play for PvP. Obviously if both players are doing the same build, a forge wouldn't be needed and you would simply have a phoenix vs phoenix match with a couple of void rays coming into play later on.