Yes, you can download it, it works and you can start playing with it, however it is a “Preview” (Back in the old days we used to call it BETA)
There are also a bunch of documents you can read to understand all the new features (trust me, there are many new things)
- Windows 8 Consumer Preview Product Guide
Download a detailed guide to the new and improved features in Windows 8 including AppLocker, BitLocker, Windows To Go, measured boot, and Client Hyper-V.
- Windows To Go Technical Overview
Learn how Windows To Go can help you provide users with bootable USB storage devices containing a copy of Windows 8, along with their business apps, data, and settings.
- Frequently Asked Questions: Managing the Windows Store
Get answers to frequently asked questions about managing end user access to, and usage of, the Windows Store within your organization.
- The Windows 8 User Experience
Learn more about application, Web, and cloud features for end users.
- Windows 8 Consumer Preview Technical Forums
Get help with questions on installation and setup, networking, compatibility, security, performance, and more.
You can read more of this here:
The download link is here:
If you need the ADK, you need to have access to MSDN to be able to download it