The LTO part runs from 14:00 to 22:00. The streaming seems to only work in Safari (for Macs), but you can download the mp4s in HD (1.2 GB) or SD (300 MB).
They do a good job of describing how it works and why this is kind of a big deal.
Google built it because it's pretty necessary to scale to the size application we build.
It looks like Apple started using it just because it's faster anyway ;)
Here are some slides from EuroLLVM last year with some pretty graphs and comparisons to traditional LTO/LIPO: http://llvm.org/devmtg/2015-04/slides/ThinLTO_EuroLLVM2015.p...
David, Teresa, and Mehdi are really amazing engineers.
(also, this is the third or so LTO system some of them have built :P)
How can Apple be shipping it (?) when LLVM is an open source project and it's not in the SVN head yet?
Is there a special branch you need to use?
A different repository perhaps?
Apple ships their own proprietary forked version of Clang+LLVM, this is for example how they implemented Swift, which was made open source long after it was introduced as part of Apple's proprietary toolchain.