There are several good reasons to always keep the OS your mini came with even if you plan on adding another by dual booting. Usually your original OS has special drivers and software to take advantage of the options a system comes with. (like the 1024X768 available with only XP on the 1010, no scrolling needed either).
The mini's come with a 160gig hard drive so there is plenty space for adding another OS. Plus the fact that most of the LInux's can be run from a USB drive or a SD/HC make space a moot point.
Instead of replacing XP on my 1010 ( I also have several Linux's) I will not upgrade ????????????? to 7 until I get my next netbook; when ever that might be. fdalbor