Both Sony and Microsoft offer a near-identical service, which serves as a means of accessing online multiplayer gaming as well as offering "free" games (as long as you remain a paying subscriber).
In Sony's case, the service is PlayStation Network; in Microsoft's case, it's called Xbox Live. They cost about the same amount of money ($60/year), and offer access to online gaming on their respective platforms. They both dole out a handful of free games to paying subscribers every month, yours to play as long as you continue to subscribe.
PlayStation Network and Xbox Live are industry standard services at this point, and barely compare. They're nearly identical. What makes each console stand out in the services department is their Netflix-like gaming services: PlayStation Now and Xbox Game Pass.
With PlayStation Now, users can stream playable over 650 PlayStation 2, PlayStation 3, and PlayStation 4 games on a PlayStation 4 or PC. The games are running elsewhere — you just start playing. It costs $20/month, or $100/year.
With Game Pass, users can download and play over 100 original Xbox, Xbox 360, and Xbox One games on the Xbox One. It costs $10/month. Better yet: Any games Microsoft publishes show up on Game Pass at launch, including the next major "Halo" and "Forza" games. It's one of the best deals available in gaming for this alone.
Xbox Game Pass is a strong argument for owning an Xbox One, and offers a glimpse into the future of video game consoles. Instead of dropping $60 per game, $10/month offers access to a massive library that includes brand new, major games. That's huge.