|   | 1 |  initial version  | 
It does seem that a sort command or option is missing. I can get closer to what you want with:
var('c0 c1 c2 x0 x1 x')
p=(c0+(x-x0)*(c1+(x-x1)*c2))
p.expand().collect(x)
This collects terms better, but they are not in order by degree.
 Copyright Sage, 2010. Some rights reserved under creative commons license. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.
 
                
                Copyright Sage, 2010. Some rights reserved under creative commons license. Content on this site is licensed under a Creative Commons Attribution Share Alike 3.0 license.