I was randomly browsing in the interwebz and found this.

http://www.examiner.com/article/kingdom-hearts-hd-2-5-remix-to-feature-new-kingdom-hearts-3d-connections

 

The thing that jumped out at me in this article is in 2.5 extra boss battles will be added.

                                           

The extra bosses are most likely the bosses from the Final mix versions(Org.XIII data,No Heart,etc.).They are new only because KH2FM and BBSFM were never released outside of Japan

Edited January 4, 201411 yr by Isaix

There have been no changes to Kingdom Hearts II Final Mix or Birth by Sleep Final Mix.

I agree that the new bosses most likely refers to "New bosses for those outside of Japan who didn't get the exclusive FM versions of BBS and KH2"

 

Considering it basically says "as a result of including the FM versions both come with extra boss battles"

I'd like to battle mroe F.F bosses. Tifa was originaly going to be a boss in KH1, but Square didn't have enough time, so they made her a NPC in KH2.

Yeah , those are the bosses from the Final Mix versions: Data Org XIII , Terra's armor-mind or something etc... I don't really see something new .

Yeah let's hope we see these Bosses when BBSFM and KH2FM for KH H.D. 2.5 Remix has been Released outside of Japan then we'll see if they have these Bosses or not.

Yeah let's hope we see these Bosses when BBSFM and KH2FM for KH H.D. 2.5 Remix has been Released outside of Japan then we'll see if they have these Bosses or not.

No need for hope we will it are the Final Mix bosses and bonusses you know.