Go is like C and Python had a kid, who inherited Python's good looks and pleasant demeanor, along with C's confidence and athletic ability.
What is Go?
Go is an open source, compiled, garbage-collected, concurrent system programming language. It was first designed and developed at Google Inc. beginning in September 2007 by Robert Griesemer, Rob Pike, and Ken Thompson. 
The creators of Go advocate a minimalist approach to language design. This minimal elegance is often contrasted with the "kitchen sink" approach of C++.
Like Python, in Go there is often "one right way to do things", although that phrase is not so commonly used as in the Pythonist community. The compiler is renowed for its strictness. Things that would at most be warnings in other languages - e.g. unused imports, unused variables - are hard compiler errors in Go. At first that may seem like a draconian buzzkill - but soon you will begin to appreciate how clean and cruft-free it keeps your code.
No question about it - Go is blazing fast. Despite a still young compiler with minimal speed optimizations, Go regularly scores at or near the top of inter-language benchmark comparisons. That's because Go is statically typed, compiled - and although garbage-collected, allows the programmer some degree of control over memory usage.
To a large degree Go follows Python's "batteries included" philosophy. Although there are not yet as many 3rd party libraries as there are for Python, nevertheless Go's standard library provides a solid foundation for many modern programming tasks. Built-in support for serving HTTP, de/serializing JSON, template rendering, and strong cryptography make Go ideal for modern web services development.
Go is frequently - and favorably - compared with Python and Ruby for programmer productivity. Its clean and elegant syntax, unobtrusive static typing, optional duck typing, batteries-included standard library, lighting-fast compiliation, and support for a variety of modern continuous integration tools make Go a productivity champion.
Since "go" is such a common English word, it is completely useless as a search term when googling. Instead search for "golang". It is standard practice in the community that all Go-related blog posts, Github repos, tweets, job postings, etc be tagged with "golang".
Who's Using Go?
- Home of the Go authors and core team, signifiant parts of the Google infrastructure are thought to be written in Go. The company however does not publicly disclose which Google services are written in which languages. Youtube is known to be powered by Vitess, an open source, massively scalable database multiplexing layer written in Go.
- Maintainers of the pq driver for PostgreSQL, significant parts of Heroku's infrastructure are said to be written in Go. One component that has been open sourced is Doozer, a consistent distributed data store.
- The company behind Ubuntu Linux recently rewrote its Juju devops management application from Python to Go, with pleasing results.
- Internet music thought leaders SoundCloud use a bespoke build and deployment system called Bazooka, designed to be a platform for managing the deployment of internal services. It is promised that Bazooka will be open sourced soon.
- Significant parts of Bitly are written in Go, including nsq, a realtime distributed message processing system.
- Large volumes of internet traffic are served by Cloudflare's Railgun web optimization software, designed to speed up the delivery of content that cannot be cached.
- Cloud infrastructure company and core Go community supporters Iron.io replaced parts of their Ruby codebase with Go, allowing them to handle a greater load with 2 workers than with 30 Ruby workers.
- Cloud-based CAD application TinkerCAD is written in Go.
- Continuous integration service Drone.io is written in Go.
- Familiarity with Python or a similar dynamic, interpreted language.
- Comfortable working on the UNIX command line.
- Basic understanding of internet protocols such as HTTP(S).
Command line examples were written on an Ubuntu 12.10 desktop environment. Everything we do in this book can also be done on other flavors of Linux, on Mac OSX - probably even on Windows.
In addition to Go language basics, this book also covers cloud deployment and continuous integration tools & techniques popular in the Go community. You will need free accounts on the following services:
- Effective Go by the creators of the language. Perhaps the single most valuable documentation resource for Go programmers.
- An Introduction to Programming in Go by Caleb Doxsey
- Go for Pythonists by Aditya Mukurjee