I believe that she will end up with Ikuto. In Doki its been showing more of ikuto and amu moments. to me Tadase (or Tadagay to me no offense) is too much a of little kid. i mean he told her he was in love with Amulet Heart then goes and says he loves her..? wtf is up wit that. And Ikuto doesnt have to say I love you everyday to tell and show Amu he loves her. I hope that she ends up wit Ikuto (he is a much better choice ^^)

At first I thought it was going to be Tadase (they always pick the princely character in anime T_T), but then I read chapter 42 in the manga and I'm on the fence again. I hope she'll end up with Ikuto, but considering the past animes I've seen, it'll probably be Tadase. link

There is proof in the last chapter she doesn't end up with Tadase. I'll explain it if you guys reading this didnot read the last chapter
Spioler~ okay. It reavils (sorry 'bout my speling) that Tsukasa is tadase and Tsukasa says to Kiseki that it was nice to see Amu again. Which proves that he doesn't have contact with her in the future with can only mean she's with someone else.
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Amu explains how she feels about Tadase
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She explins how she feels about Ikuto
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