Standout points in my opinion:
Overall performance improvements:
>> "We observed a 5–35% speedup across our benchmarks."
Decreased compile times and binary size:
>> "While these changes across the compiler toolchain are mostly invisible, users have observed a significant speedup in compile time and a reduction in binary size by as much as 20–30%."
Vendoring dependencies by default:
>> "...and in Go 1.7... the "vendor" behavior is always enabled"
Context package added to std lib:
>> "To make use of contexts within the standard library and to encourage more extensive use, the package has been moved from the x/net repository to the standard library as the context package."