Forwarding Ubuntu Precise Beta 1 announcement:

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This release introduces a new set of images for the ARMv7 "hard float" ABI, denoted as armhf. There are still some armel images around, as we finish the migration, but 12.04 for ARM will be based on armhf.

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Ubuntu Core -----------

Ubuntu Core is a minimal rootfs for use in the creation of custom images, and now includes ARM hard float (armhf) images. Developers can use Ubuntu Core as the basis for their application demonstrations, constrained environment deployments, device support packages, and other goals.

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Full announcement available on https://lists.ubuntu.com/archives/ubuntu-release/2012-March/000899.html