The AMD Zen/Ryzen reviews and benchmarks are hitting the web (Ars has a review and a look at the Zen architecture, Tom's Hardware has a review, and there's bound to be more), but as always, the one you want is AnandTech's (they also have an interview with AMD's CEO):
For over two years the collective AMD vs Intel personal computer battle has been sitting on the edge of its seat. Back in 2014 when AMD first announced it was pursuing an all-new microarchitecture, old hands recalled the days when the battle between AMD and Intel was fun to be a part of, and users were happy that the competition led to innovation: not soon after, the Core microarchitecture became the dominant force in modern personal computing today. Through the various press release cycles from AMD stemming from that original Zen announcement, the industry is in a whipped frenzy waiting to see if AMD, through rehiring guru Jim Killer and laying the foundations of a wide and deep processor team for the next decade, can hold the incumbent to account. With AMD’s first use of a 14nm FinFET node on CPUs, today is the day Zen hits the shelves and benchmark results can be published: Game On!
Gaming performance seems to lag behind Intel, while for workstation tasks, it has them beat. For me, an upgrade to Ryzen from my i5-4440 would amount to a total sum of about €900 (processor, motherboard, RAM, and cooling), so I'm going to wait it out for now - especially since gaming is what my processor is most used for. That being said - give it a year, and Ryzen will be up there on all fronts with Intel's best, but at a lower price point.
AMD is definitely back, and I'm very excited to see what competition will bring to the market.