Yes it does. In fact, it was the first computer to coin the phrase "ROM" and the only one that actually does it properly.
First off, wrong. The AX91B's rom system functions in the same manner--- Dup the brick into the rom slot, and boom. Furthermore, roms for the AX91B can accept and use input from the computer without the use of referencing named bricks, unlike the IceCube. This provides unlimited possibilities for ROM's. Albeit true that the IceCube is the first to use ROM's, it is no longer true that it is the only one that does it properly.
Another thing about my rom system, it also checks weather there's a rom in the slot or not, and has 4 fully functional slots, each able to be launched individually from the Rom Manager app.
In my opinion that tops the IceCube twofold.