It's natural for GEASS characters to be losing ground; they can't stay there forever. Though, I still cannot believe they have SEED characters in the top 10. There are many other good shows going on. For example, I see many D. Gray Man characters, whereas not a single Soul Eater character, which I think is strange, seeing as the shows have similar premise, but Soul Eater is newer.
Other than that is seems like the vote numbers for Animage and Animedia are not very high - in the 400s for the top spots and the 100s for the top 10. They seem pretty much in the same league as the number of votes in Animesuki. Thus, I don't think they hold as much "weight" as for example the Newtype ones.
Another interesting thing is that in mixed-gender popularity polls almost all of the top 10 are guys. It seems totally contrary to the views in Animesuki, where almost all the top 10 are girls. See for yourself:
http://forums.animesuki.com/showthread.php?t=72602
Any idea why this is the case?