Just adding my own 2 bits...
This statement isn't exactly true. Here is number of C / C++ in top 10 in past contests:
PCR - 1
PR - 4
PR2 - 2
TGE - 7
BTTC - 6
CvZ - 4
CSB - 5
STC - 9
CB - 4
HS - 10
TAC - 8
Overall - 62% of top 10 from these 11 contests were C++ (35% of first 4, 78% of most recent 4)
I think that there's several elements at work here that contribute to these trends:
1) C / C++ gives somewhat of an advantage over most other languages. I'm not going to debate this point, but I don't think it's as significant (in most contests) as most people imply that it is.
2) Some contests heavily favor processing speed, namely STC.
3) CG veterans know that some contests favor C++, and so they tend to write contest code in C++ from the get-go, just to ensure that they're not at a disadvantage.
4) Superstitions and rumors about the unbelievable power of the C++ abound.
5) More and more of the elite competitors write solutions in C++, so more of the top finishing AIs are C++ AIs.
6) Snowball effect.
7) Cue whining and pleas for overcompensation.
CG isn't an intelligence ranking. It's a coding skill ranking. The very best coders are intelligent, yes, but they are also skilled at many languages. The very best coders are versatile. The very best coders choose the very best language for a task. The very best coders learn from failures and do whatever it takes to improve, including learning a new tool if that's what's required.
My vote: Don't handicap based on language selection.