Ok, I don't think there's much differences. With 7 you lose the "Always on top" option for your windows, but there's a widget you can download to get it back. The half screens are great if you have a large screen, but on a normal size laptop I don't use it that much. ummmmmmmm you have to use a separate e-mail provider, like Mozilla Thunderbird, because outlook express isn't on 7, other than that not a lot of difference. I didn't have to back up anything, and didn't lose anything during the switch. I don't remember it taking that long time-wise to do.