I've been having a ton of success with this build since I saw and studied it a lot at MLG Orlando. It keeps Protoss even with the Zerg economy, and functions much the same way the old 3-gate expand build used to go - we're just starting with an additional base to work with. I feel like this build is incredibly flexible and probably the best safe macro build you can opt for right now. It's also fairly easy to execute.
The gist of the build is this:
I make 1 zealot and send it straight to Zerg's main to scout.
make nothing but sentries, get +1 weapons and warp gate.
chronoboost probes a LOT. almost exclusively, in fact.
make a total of 6 gates, as if you were doing an all-in.
If Zerg scouts this, he'll cut drones and start producing units and spines in anticipation of the all-in. I've had Zergs overreact so badly they cancel the spire or whatever tech they have building, cut drones at 50 for several minutes, and make 6 spines. This is an added bonus but not at all necessary for success! If Zerg doesn't scout this or your zealot sees some greedy tech like mutas, you can actually choose to all-in here.
As soon as warp gate finishes, warp in sentries (up to 8-ish then stop) and zealots. Right around the 8:30 or 9 minute mark, when warp gate finishes, make the 3rd base. I like to push out at this timing to make Zerg think I'm doing the 6-gate all-in - make sure to include a probe so he'll buy it!
We have to rely on forcefields, cannons, and building placement to survive roach-ling aggression right now. Just like the 3-gate expand - except instead of trying to secure the natural expansion, we're securing our 3rd. Zerg has a 3-base economy to pressure, but we have a 2-base economy and 6 gates. To pressure the expo Zerg has to forgo drones, which is great for us, as long as we survive.
As soon as 3rd base is secure, make robo facility and twilight council simultaneously. This gives a ton of flexibility. Make an observer as soon as the facility finishes.
At this timing is when Zerg's tech will reveal itself. See a flock of mutas? Start blink and make a templar archives. See roach pressure? Start that robo bay! If Zerg hasn't made his presence known at this point, and you haven't pressured to check his army comp, just start the robo bay AND blink. No big deal. Get up to +3 weapons before beginning any armor upgrades. If he goes mutas, delay colossus production in favor of blink stalkers and possibly psi storm. The mutas won't deny our 3rd base because it's already up and running. Just prevent any major damage.
At this point we kind of just sit until we're maxed. Take a 4th AND a 5th base at this timing while you get aggressive (the main and natural should be drying up soon). The maxed protoss army is fearful as hell. You should have 4-5 colossus and a ton of blink stalkers with 8 full energy sentries; OR you should have a bunch of templar with storm, blink stalkers, and possibly some immortals. Whatever you have to do based on what Zerg is making. This is also when you can add a dark shrine and whatever other tech you want to. Assuming you got to this point relatively unmolested, you SHOULD win the game.
This build has some problems, of course. It's weak (like most Protoss builds) to huge infestor-ling attacks when you're securing the 3rd and teching up. It can be weaker to certain early all-ins because there's no stargate tech. The build also only works on maps with an easy-to-defend 3rd base. Building sim-city and cannons are an absolute requirement at the 3rd.
Check out Huk's PvZ from MLG Orlando! All their replays can be found here: http://pro.majorleaguegaming.com/news/mlg-orlando-sc2-replays-get-them-now