Language Details: Go

Go is a fast, statically typed, compiled language that feels like a dynamically typed, interpreted language.

Official website (see also: Wikipedia article)
Code Jam 2012 Contestants using Go
Qualification Round
Used in 125 solutions by 42 contestants:
Round 1A
Used in 12 solutions by 3 contestants:
Round 1B
Used in 5 solutions by 3 contestants:
Round 1C
Used in 7 solutions by 4 contestants:
Round 2
Used in 2 solutions by 1 contestants:

Submission Origin

United States (14 contestants)
Japan (4 contestants)
Brazil (3 contestants)
France (3 contestants)
United Kingdom (3 contestants)
Australia (2 contestants)
New Zealand (2 contestants)
Canada (1 contestant)
China (1 contestant)
Germany (1 contestant)
Greece (1 contestant)
Israel (1 contestant)
Latvia (1 contestant)
Poland (1 contestant)
Portugal (1 contestant)
South Korea (1 contestant)
Sweden (1 contestant)
Switzerland (1 contestant)
Ukraine (1 contestant)