This 2v2 strategy is one of the most effective ways of reaching the Plat/Diamond tiers with the minimal amount of time. A buddy of mine and I went about 30 wins to 2 losses using this strategy about a month ago. It has now become extremely popular so its effectiveness has been reduced but it is still really powerful in Plat leagues and below.
Beware that implementing this strategy means that when you finally do start losing games you will not have the requisite skill level to take on your opponents since you cheesed your way into the higher leagues =(
The killing blow comes from the Protoss player who will warp in zealots directly into the enemy base. This is achieved by having the Zerg player provide vision with the overlord and protection/harass with the 24 speedlings produced at around the 5 minute mark.
Build order and replays after the jump.
The Protoss build order:
10Pylon -> scout
Chrono Boost probes once
13Gas - 3 workers , stop harvesting after 50 gas
15 cyber - warpgate when done. Chronoboost 4 times
18 Proxy pylon
18 Proxy pylon
18+ Warp in zealots and build pylons
The Zerg build order:
10 Extractor (start the extractor when you have 100 minerals) 2 workers on it. Stop when 100 gas
11 Queen - only use for larva inject
14 Zergling speed
15+ Zerglings and overlords
-As soon as game opens send the overlord to the ideal warp-in location. Don't put him too close to the enemy base or he may get sniped/scouted.
-Around the 4:40-5min mark you will have 22-24 speedlings. Send these out to harass or protect the Protoss probe depending on the chances you give on having probe attacked by early lings or marines.
-Afterwards, continue producing speedlings or expand. Expanding is a last resort option since you have really committed yourself to the rush.
-Around the 5 minute mark send a probe by the Zerg overlord to warp-in location. You will have two warp-in locations, one for each enemy base. Warp-in zealots zealously FTW.
Effective Counters to the Speedling/Warp strategy
Considering that the Protoss player has absolutely no units in his base until he starts warping around the 6:30 minute mark, you absolutely must attack before that time. A good general strategy would be to 2 Gate as Protoss, 2 Rax as Terran, or 9 Pool as Zerg. Any early pressure to the Protoss will do. Remember that you must hit him before the 6 minute mark.
French dude on youtube implementing in 2v2
Credit goes to Geiko for creating this build order.