Windows 10 Build 10074 is available right now directly from Microsoft in ESD form, and you can download them directly from Windows Update. We're not sure if Microsoft is going to keep the links up for long, so I'd get downloading if I were you. Keep in mind the build is an ESD file, meaning it needs to be converted into an ISO file which can be done via an ESD decryption tool.
Beta enthusiast site OSBetaArchive have the links to the WU server ready to go. As said above, get downloading quick as Microsoft could pull said links at any given moment. Build 10074 includes a number of features and changes over build 10061, including an improved Cortana UI and more. You can check out our hands on video below.
Microsoft will be unveiling a number of new features and announcements at its BUILD developer conference tomorrow. Stay tuned at WinBeta for more coverage.