People who seen it or played it keep comparing ARMS to Punchout. It's a bad comparison. Yes I can see why at first one might think that. Behind the back view and you punch plus some boxing gloves involved. However Everything else is quite different. You have an arena based fighting game. We don't see many of these anymore. Notable game sin this style have been Virtua Fighter and Soul Calibur. Another thing ARMS does is while you are punching,it's closer to shooting. You must take aim to punch or fire. We saw a new character in the the April 12th direct with a laser so we do have characters with projectiles. Last this game uses both analog sticks when using traditional controls. So it is in fact a Twin Stick fighting game.
So what is ARMS a clone of? Virtual On series.
Now ARMS seems a bit more stripped down but everything said above is the same. Arena fighter. You aim and shoot. You use dual sticks to fight (Arcade & 360 port I think). From Siftware also made a robot arena fighting game called Frame Gride.
So anyone who thinks ARMS is a more quirky looking Punchout is wrong. It's a more Quirky Virtual On. That is a great thing as the VO games were amazing.