If the plasma panel is on the bottom and you add the kickoff menu, the power actions are at the bottom. When I have a panel on the side of my screen, even if the kickoff menu is on the bottom of the panel and basically the same place as it would be in a bottom panel, the power action suddenly is on the top, which, at least to me, looks a bit weird. If this is done on purpose, it would be really nice if there was a setting to chose whether it's displayed on the top or the bottom.
*** This bug has been marked as a duplicate of bug 433241 ***