I have added a comment in the talk page, this will break the XO. It is not an i686 compatible CPU. It is i586 with the addition of cmov. rpm correctly refuses to install i686 rpms on the system. the OLPC compose tools shove i686 glibc and openssl on but they are not updateable.
FESCo has approved this proposal with some revisions. i586 support will be retained for F11. Mass rebuild with rebuild to .i586.
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