HDMI Forum, the trade association that determines and licenses standards for the HDMI video connection, has announced HDMI 2.0. It's much, much faster than the current HDMI 1.4 standard, with a bandwidth of 18Gbps and support for 4K (or Ultra HD) video at 60 frames per second. This is a big technical jump over the current HDMI standard, and it's big news for future HDTVs. However, if you think of HDMI as mothing more than "that cable that connects my HDTV to other things," these changes will seem confusing and esoteric.
"But Will, I'm just a humble layperson who enjoys media consumption! What does HDMI 2.0 mean to me?" I'm glad you asked, humble layperson. Let me put your fears at rest.
It means nothing. Right now, for you as a consumer, it means absolutely nothing. Don't worry about HDMI 2.0. It will be a major factor in the future when 4K (Ultra HD) HDTVs become more commercially viable and native 4K content becomes more available, but right now the HDMI standard means nothing. For your current HDTV, Blu-ray player, cable box, media hub, and game system, don't fret about looking for HDMI 2.0 cables or having to replace all of your wiring.
Your current home theater components don't support HDMI 2.0 and never will. They don't have to, and have been built around the capabilities of HDMI 1.4 (or earlier, if they're older components). Even if they support 4K video, like the Seiki SE50UY04, they support it with the bandwidth HDMI 1.4 offers, which allows up to 24 frames per second. Future HDTVs, Blu-ray players, and other electronics will eventually incorporate HDMI 2.0, but it's nothing you have to worry about with your current components.
I have some other good news: When you do get new electronics that support HDMI 2.0, you won't have to replace your cables at all. Every electronics store will sell new, expensive HDMI 2.0 cables, but you don't need to buy them if you already have HDMI 1.4. This is purely a new standard at the electronic component end, and any HDMI 2.0 cables you buy next year will be effectively identical to the HDMI 1.4 cables you already own. As long as your HDMI cable is "Category 2," which is the only designation you need when selecting HDMI cables, it will work. Don't let any electronics store clerk tell you otherwise. In fact, I'll quote the HDMI Forum's own summary of HDMI 2.0:
HDMI 2.0 does not define new cables or new connectors. Current high speed cables (Category 2) are capable of carrying the increased bandwidth.
Take that to heart when you want to upgrade to a 4K TV or get a new game system. If your HDMI cables are already high-speed and can send 1080p video at 60 frames per second, They have the bandwidth to carry 4K video at 60 frames per second if both the HDTV and the source are HDMI 2.0-compatible.
HDMI 2.0 is still something to get excited about, just not for your current home theater. HDMI 2.0 represents an official standard for sending 4K video at 60 frames per second over a cable. This is something we haven't seen before, and it's an important piece of the 4K HDTV puzzle. With 4K screens becoming available and a 4K standard set for HDMI, all we need now is a universally agreed-upon 4K media standard. Once an optical media or digital distribution trade group cane come to a decision about how to best get 4K movies to consumers, whether it's multi-layered Blu-ray, holographic disc, or flash memory card, we'll have everything we need to watch 4K movies without getting an entire file server from an HDTV manufacturer preloaded with a handful of films. The 4K screens were the first step, and HDMI 2.0 is the second step. When we have media ready for it, the 4K revolution will begin.
Just don't throw out your HDMI cables when it happens. You'll still be able to use them.