Just finished the Preview Build update on a Hyper-V testbed.
I was taken to the Welcome page when I launched IE: Welcome to the latest Internet Explorer
Today, we are rolling out a new Technical Preview build to Windows 10 Insiders. This build doesn’t have Project Spartan yet but it does have many updates to the new web platform that Project Spartan will use. We look forward to your feedback!
The IE welcome page also had a What's new link: New features and fixes in the January Insider Update
We started testing our new rendering engine by rolling it out to a portion of Insiders using the Windows Technical Preview in November. Since that time, we’ve gotten over 12,000 feedback reports through the smiley face icon alone. This new build has over 2000 changes to the new platform, largely influenced by that feedback. In addition to many fixes, there are also several new platform features that we are thrilled to be releasing today:
On the Insider Home page: What's new with the Windows 10 Technical Preview
but... I couldn't watch the video in Win10