Not all handsets are included in the chart. The Geekbench Browser has a list of handsets which it uses to build the benchmark chart. This list contains model and processor information and is manually maintained; if a handset isn't in the list, it's not included in the chart. I thought all of the S3 models were included in this list, but apparently I'm wrong. I'll make sure this list is up to date.
Geekbench is built with the NDK (since all of the benchmarks are written in C or C++). There was a bug in Android 4.0.3 and earlier that caused Android to select the ARMv5 libraries instead of the ARMv7 libraries (which caused a massive drop in performance). This was fixed in 4.0.4 which is why there's a huge jump in performance between the two versions on the One X.
Shouldn't results from the One X on 4.0.3 (or even all results from 4.0.3) be excluded from the averages then? In the case of the One X the average is ~1000 but without the ~600 scores in there the average would be much closer to ~1500.
Geekbench is built with the NDK (since all of the benchmarks are written in C or C++). There was a bug in Android 4.0.3 and earlier that caused Android to select the ARMv5 libraries instead of the ARMv7 libraries (which caused a massive drop in performance). This was fixed in 4.0.4 which is why there's a huge jump in performance between the two versions on the One X.