LAS VEGAS — To understand the importance of the Consumer Electronics Show, consider this: the mobile devices everyone carries and most of the entertainment hardware in living rooms worldwide were launched here first.

Every January, the major electronics manufacturers trek to Las Vegas to unveil their latest consumer gadgets, and for Hollywood that’s meant new platforms on which to distribute its films, TV shows, music and games, along with other content.

The major entertainment players have caught onto that, with the last two years seeing a surge in registered attendees from the biz (9,000 participated in last year’s Entertainment Matters program, co-produced by United Talent Agency with the Consumer Electronics Assn., and that number is expected be larger this year, the orgs say).

This year’s show, which ran Jan. 10-13, attracted around 150,000 attendees who visited CES’ 2,700 exhibitors.

Hollywood execs came to seal deals with hardware makers, but they’re also looking to see what’s about to roll out to retailers.

In the past, those new items have included the VCR, Laserdisc, CD, DVD and Blu-ray players, HDTV, LED and 3D TVs, MP3 players, smartphones, UltraViolet and tablet computers, to name just a few.

“Nearly every consumer electronics innovation in the history of our industry was unveiled at CES,” says Gary Shapiro, president and CEO of the CEA.

Worldwide consumer electronics spending is expected to pass $1 trillion this year, according to GfK Boutique Research and the CEA, up 5%. Sales are expected to top $200 billion in the U.S., where consumers spent $190 billion on electronics last year, up 5.6% from 2010. In short, Hollywood can’t afford not to pay attention and be present at CES.

“We’ve been saying this for the past 15 years,” Shapiro says. “We’re not just a hardware show. We have people here from every aspect of the industry.”

And here’s what everyone has been looking at as the top trends coming out of the show this year:

• Ultrabooks: Intel coined the term to describe thin, fast laptops that imitate Apple’s MacBook Air. These devices save data on chips, instead of traditional hard drives, and access the cloud for content. Analysts expect the devices to represent 10% of all laptop sales in 2012. More than 60 manufacturers are making Ultrabooks to release this year.

• Smart TVs: While they had been introduced at CES in previous years, the new batch that Samsung, Sony, LG and Panasonic revealed this time around are still focused on filling up the screens with apps, but also sport features familiar to owners of Nintendo’s Wii and Microsoft’s Xbox 360, as well as users of Siri on Apple’s iPhone 4s: gesture and voice controls.

And why not? It’s estimated that Apple sold more than 30 million of its newest phone in the fourth quarter, and Microsoft has sold 18 million Kinects.

Samsung has added facial recognition to cameras built into its sets to recognize who is using its new line of TVs and help them access their apps. TV-makers hope the features will help them boost sagging set sales, which the CEA projects will decline 6.5% this year.

• OLED and 4K TVs: The next high-def TVs on the market will feature super-thin screens (LG’s 55-inch set is 4mm thick) and boast brighter, crisper and more colorful images.

• Cheaper tablets: Most tablet-makers are introducing smaller, cheaper tablets to compete not with Apple’s iPad but with Amazon’s Kindle Fire and Barnes & Noble’s Nook. Tablet sales are expected to triple to 55.2 million this year, according to Juniper Research.

Not all new product have been instant hits at CES.

3D TV got a big push in 2010, and while the sets are selling overseas, they’re still struggling to catch on in the U.S.

Approximately 30% of consumers still say they have no immediate plans to purchase a 3D TV within the next six months, citing price and the glasses as reasons, according to NPD Group. (Glasses-free 3D sets aren’t expected to be developed within the next year.) The research firm also says 3D TVs made up 9% of all U.S. flat panel TV sales through November, up 2% over the same period in 2010.

Although, sales of 3D TVs are soft in the U.S., 23 million 3D TVs are expected to ship worldwide this year, with more than 100 million units to ship by 2015.

While 17 million smart TVs have already made their way into homes, only 10% were connected to the Internet last year, up from 8% in 2010, research group Parks Associates says, because many consider the TVs confusing to use.

Meanwhile, netbooks, introduced in 2009, were designed to serve as inexpensive laptops that connect to the Web. Apple’s iPad pretty much did away with that category.

Last year, more than 100 manufacturers introduced their own tablets to compete with Apple. Most, like BlackBerry’s PlayBook, have struggled or failed, with HP pulling the plug on its TouchPad after dismal sales. Samsung’s Galaxy Tab still remains a worthy rival.

Apple doesn’t attend CES to showcase new products. It eschews trade shows to host its own events throughout the year, although it did send nearly 300 staffers this year, sources confirmed. Microsoft will be the next to leave CES after this year’s confab, ending a 15-year appearance.