Comment More information. (Score 4, Informative) 135
The summary is terrible. And not just the invalid link.
Here's a more informative link than the one posted by lnunes.
Multiarch is not gonna let you run ARM binaries on an Intel chip or anything like that - nor will it let you run Windows code on Debian. What it will do, however, is let you run x86 compiled binaries on an x64 system. It will also allow for things like mixing armhf and armel code on modern ARM, but for the most part, running 32-bit x86 code on 64-bit x64 (amd64) systems will be the benefit most of us will get.
How will we benefit? You'll be able to run binary-only x86 code on your x64 system. This means Adobe Flash and Skype. Any open source code is fine, because it can be compiled for your own architecture - but for binary-only proprietary software, it may not be available for your architecture.
"But this is already possible" you may be thinking. It is, but it's a nasty kludge at the moment. These packages, when installed on 64-bit systems, depend on 32-bit versions of several system libraries, which are separate packages. There's a series of kludges to make them work, and it's not very flexible.
The heart of multiarch support is a re-designed file system layout which accounts for the architecture of any binaries. So instead of putting some binary libraries in