Ok here are some impressions on Jump Super Stars from a Japanese guy who was at Jump Festival.
Original source:
http://d.hatena.ne.jp/djfort/20041219
It indeed uses the Smash Bros system of Coin battle, including Ring Out, etc. The controls are as such: Y = weak attack, B = strong attack, A = Special A, left/right on d-pad + A = Special B, down on d-pad = guard, X = jump.
The touch screen shows manga panels and is known as the "Manga deck", this shows all your characters of 3 different types. Battle Characters (Goku, Boobobo, etc), Support Characters (Light Yagami w/ Ryuku, Chopper, etc) and Item Characters (Torpedo Gaal, Holy beans, etc).
Battle Characters are the ones you actually control in the battle and you only control one at a time. There is a Jump Spirits Gauge, which drains as you use special attacks, when it runs low and you can't do specials you can tag out with the touch panel. Characters not in battle slowly regain their gauge.
Confirmed characters:
Battle - Son Goku (DBZ), Monkey D Luffy (One Piece), Uzumaki Naruto (Naruto), Boobobo (Boboboobo Boobobo). It seems that in one deck you can have a maximum of 3 battle characters.
Support - Ichigo 100% no Ko (Gomenasai Attack), Toni Toni Chopper (Treasure chest), Light Yagami/Shinigami Ryuku (Going berserk with the Death Note). Support characters also have a JS Gauge so you can call them out as many times as you want.
Item - Torpedo Gaal (Speed up), Holy Bean (J Spirit recover). Items are limited by quantity.
So to sum it up, each battle character has 2 special attacks, support characters are non-controllable and have special support functions, items are limited stuff to boost your active characters, you can swap characters in and out of battle with the touch screen, the game uses the Smash Bros battle system.
Hope that was helpful to those looking for some new info from Jump Festival... I know it's really limited especially this year.
