People realise that apple fans are used to colourful UI on their phone right? If samsung want to nab more of that market share they have to make the samsung UI appeal to the people that would buy apple in the first place hence touchwiz.
Tbh i am done with small phones now, this nexus4 is annoying me i really want to make the move to a bigger screen so i am hoping to finally get myself one of the note line when my contract is up in april, hopefully note 4 will be out eh.