Except that Java code typically runs as fast or faster in the JVM than compiled Go code[1]. Of course, Go is still new and gc and gcc-go will be optimized further.
But Java bytecode execution is definitely not slow and usually within 2x the execution time of a C implementation, which is faster than the vast majority of other language implementations.
[1] At least in the language benchmarks game. Yes, I know that microbenchmarks are not representative, etc. etc. etc. (Until your favorite language is faster ;).)