Well...
48 edge to corner magnets
16 corner to core magnets
24 edge to core magnets
12 maglev rings
thats 100
but someone could also add 48 more magnets to the edges and corners to increase magnet strength, and add 20 more to increase the edge/corner to core magnets, and they could also do 24 more magnets that are center to edge.
so i think the most in a 3x3 is somewhere around 148 to 192