This is an interesting development. Ubuntu throws their hat into the ARM race - at first apparently mainly for servers. But it is another indication of the significance of this architecture for the future. The Windows8 developments should be seen in this context.
Canonical has confirmed that the x86 and x86-64 versions of Ubuntu Server 11.10 will be joined by a version for ARM-based architectures. The company believes that ARM servers will become important to data centres because of the architecture's history in low power consumption applications such as smartphones.