In case you haven't heard of the Burj Dubai [wiki], it's the next world's tallest skyscraper which they've been building in Dubai for the last few years. What makes it so notable is that it's way taller than any previous record holder. It's 2,717 feet tall, whereas the previous "world's tallest building" is over 1,000 feet shorter (Taipei 101 [wiki] at 1,670 feet).
I'll go on about that soon, but first here's a video with a really cool view from the top. Like, the top top. The guy's on top of the highest spire. It looks more like a view from a plane than a building:
The reason I say "world's tallest everything" is because I always remember people having to make distinctions about, say, whether the Petronas Towers or the Sears Tower was the "world's tallest building" because of rules like measuring to the highest occupied floor or the "architectural top." And beyond that they had to distinguish between saying "world's tallest building" (Taipei 101 [wiki], 1,670ft), "world's tallest freestanding structure" (Guangzhou TV Tower [wiki], 2,001ft), and "world's tallest structure" (KVLY-TV antenna [wiki], 2,063 ft) because of more distinctions like having occupiable floors (building category) or not being stabilized by guy wires (freestanding structure category). All that stuff made the buildings' records a lot less cool. Also, the "tallest building" changed like every few years for a while with the Petronas Towers [wiki] being built, then Taipei 101, then the Shanghai World Financial Center [wiki]. Each time it'd go up by like a few dozen feet.
So I'm glad they finally made one that's indisputably the best at everything, period. And it will be for a while.
This chart shows how hard it'll be to top:
Update: I came across a blog post that describes very well the confusion and nitpicking about tallest structures. The Burj Dubai: The Biggest God Damn Building In The World by Everything Everywhere