The main keynote that will kickoff the CES 2014 event will be reserved to Sony. Sony won the best smartphone at the show last year with the Xperia Z, so they clearly deserve to be one of the companies who would hold the main keynote. Their own event at CES last year was also only second to Samsung, in terms of size. Sony wanted to send a message that they're coming for Samsung, because they can be just as good as they are. In 2014, they may just get the chance to prove it, but they will need to come to US first, and this US-based keynote might help with that.
The US market may not be the largest market out there, and it's certainly not the easiest one, with Apple alone having about 40 percent of it, and the rest being split mainly by other Android companies. It's bad enough that the market is as saturated as it is, but OEM's also have to deal with the historically "not very nice" carriers, who will negotiate with them until they are barely making any profit, unless they are huge and very popular, like Samsung is.
They are especially unfriendly to newcomers into the US market, and the carriers won't let them sell in their stores and on their networks, until the OEM's give up a huge percentage of the phone's revenue. Rumors were, for example, that the Moto X was being sold to carriers for $350, while they were charging $200 for it on contract, and almost $600 unlocked. Compare that to Apple, who gets to sell the phone to the carriers at full price - $650. When Apple gets away with a deal like that, and the carriers bleed everyone else dry to compensate, no wonder the US market isn't very profitable for most Android OEM's.
The carriers will also take a new OEM on their network, only if they know their phones are going to be popular all over the world, which could also mean they will be popular in US. That's part of Sony's strategy to save their money and not come to US right now, until they make their phones very popular across the world.
Another way they could really become popular in US, and with US tech media, which a lot of non-Americans read, too, is to make a Nexus phone for Google next year. That strategy helped LG tremendously to the point where they are being taken seriously now by both consumers and the US tech media, which in turn led to them being taken seriously by the US the carriers, and allow them to sell their phones on their networks.
In the end, whether Sony will make a Nexus next year or not, will depend on Google, but if Google wants Samsung brought down a notch from their position in the Android market, Sony is the company to bet on, right now.