Nine minutes and fifty one seconds. That's all speedrunner linkdeadx2 needs to blaze through Super Mario World, and it's a treat to watch him do it (in Mario PJs, to boot!)
This is an 'any percentage' run, which means that a player doesn't need to get 100% completion to beat the game and claim a time.
The leaderboard runners-up at this time are xpaco5 and dram55, with 09:51.12 and 09:51.69 runs, respectively. Milliseconds can make all the difference in a speedrun; thanks to milliseconds linkdeadx2 has the world record for beating Super Mario World quickly.
You can read more about Super Mario World speedrunning, including tricks and glitches, here. Especially useful if you're curious as to how this speedrunner had a cloud for the final fight against Bowser, a glitch used in this run:
You must be small Mario to do this trick. Various powerups have various effects on what happens when you do this.
In Yoshi's Island 2, you get Yoshi, and grab the next red shell you see.
Aim to spit the fire so that the middle flame is lined up near the top of the two large bushes.
You must shoot the red shell before the green shell spawns. If you shoot too late, you won't be able to item swap.
Grab the green shell, and jump to the third step in the hill ahead.
Holding down, spit out the shell so that it's sitting still in front of you.
Turn and face left, stopping a little bit before reaching the middle of the step you are on. You want to be facing left right up until you dismount Yoshi, as you jump further right this way.
When the coin is about to land (Roughly, when it touches the bush in the background), tap right, and quickly roll your thumb from X to A. Yoshi should turn around, stick his tongue out, and you should spinjump to the right
Immediately let go of these buttons and hold R
If everything works perfectly, you'll end up with a garbled graphic in your inventory box. This is the cloud! You're going to want to hang onto this until you get to the fight with Bowser, so don't collect any midpoints, because when you grab the cape, you'll overwrite your cloud with a mushroom.
Fascinating stuff.