Shouldn't that be 100+ times greater? Each whole number increase is tenfold, so a 9 versus 7 would be 10x10 or 100 times greater.
You are probably right - it seems a bit confusing - originally, it was just supposed to be 10x but then there are different sets of values which seem to indicate 1000x or 100x depending. Just lets say significantly greater.
Aside: The 10x scale is how the Volcanic VEI is reported