Two days ago, on November 24th, Canonical announced through Steve Kowalik that the LPIA architecture would no longer be supported, starting with the upcoming Ubuntu 10.04 (Lucid Lynx) operating system. At the moment, support for the LPIA architecture is still available on the Ubuntu 9.10 (Karmic Koala) release. Because many users are not interested in this Low-Power Intel Architecture, the developers decided that it was better for everyone (upstream developers, Ubuntu developers, community members, third-party developers, Canonical support stuff, etc.) to retire it.
"During a discussion at the Lucid Lynx Ubuntu Developer Summit on the future of the architecture, all participants agreed that retiring the architecture would be a net benefit to Ubuntu. Several participants volunteered to investigate the performance and power consumption of lpia vs. i386, with the intention of bringing these improvements forward in future releases." - Steve Kowalik said in the official announcement.
Canonical added support for LPIA a couple of years ago and it was used by the Ubuntu Mobile project, for the recent Intel mobile CPUs with support for this lower-power architecture. The LPIA or Low-Power Intel Architecture is similar to the IA32 (also known as i386 or x86) architecture, but with dissimilar compile-time optimizations. However, Steve Kowalik added that the Intel CPUs would work very well with IA32: "Recent announcements by Intel indicate that processors supported by the lpia architecture are expected to remain compatible with the IA32 instruction set, so there is a reduced expectation of the need to retain a separate architecture to address future requirements. As of 9.10, lpia and i386 share the kernel configuration, reducing most of the benefits potentially available in previous Ubuntu releases."
Support for the LPIA architecture will be provided on the Ubuntu 9.10 (Karmic Koala) operating system until April 2011. But existing LPIA users will not be able to upgrade their system to Ubuntu 10.04 LTS (Lucid Lynx), when it will be released on April 2010. Moreover, Canonical does not recommend that older (Ubuntu 9.04 and lower) LPIA users upgrade their machines to the Ubuntu 9.10 release due to its poor maintenance. Instead, they are encouraged to try the current i386 release of Ubuntu 9.10 (Karmic Koala).
Canonical Drops Support for LPIA on Ubuntu 10.04
The Low-Power Intel Architecture no longer with Lucid Lynx
... so hot right now