It's supposed to be sort of roof/chimney like I think. Since it's the familitchi it makes the V5 and V5.5 look more like a home. It is bulky, but I understand why they made it that way.
Thought it surprised me when the Music Star came out and there is no antenna.
Basically it there for looks.... If I had a cover for the edge... I would cut it off. It is of no importance as are the older antenna. They are all there just for looks...
(Bit off topic but.....)
If you are/were a digimon fan of Season two, It reminds me of the season digivice. Maybe they were trying to sorta "recreate" it. It was a HUGE seller, maybe they were trying to get it again...0_0;
-Back on topic-
They didn't need the antenna if they were recreating it to be like that.... It totally fits, right? People were waiting for years for them to be back on the sale shelves.