I saw this episode yesterday on Youtube, ( which I wish they at least made it with Subtitles, can't understand japanese at all lol ), and it was surprizing to me that Aipom did'nt even have any form of doubt about the trade, nor did Buizel, almost like they knew it was going to happen >_>' ( grrr writers...) But I think that even if Aipom is Dawn pokemon now it will still love Ash regardless of who it belongs to. I still think Aipom will still steal Ash's hat from time to time. But omg! From the way Ash commanded Buizel in their first battle together was amazing! The Same for Aipom and Dawn! Aipom will always love Ash even if it belongs to Dawn, the same for Buizel and Dawn, but Buizel seems to really like Ash, not only for his battling attitude, but about the amount of care and trust he will give to him.
So Ash finally gets a Water type ( a powerhouse at that ), and new Friend, and Dawn gets Aipom, who will love Dawn the same as it loves Ash, and get contest battler. You know? Aipom is a powerhouse too, such Dawn did'nt lose a powerhouse, she just gained a new powerhouse! And the end of the episode when Aipom jumped on Dawn's head, and Buizel sparring with Pikachu was very cute. Great end to a great episode!