12.04 LTS: 64-bit desktop by default? - how about 13.04?

[Alan Bell]

another consideration is that the computers that don't do 64bit are less 
likely to have enough 3d acceleration to run unity in hardware OpenGL so 
are more likely to fall back to llvmpipe and they are not going to like 
that at all on an elderly CPU. I doubt we run well at all on anything 
that can't do 64bit.

Alan.

-- 
I work at http://libertus.co.uk