Clearly Xbox. Just look at the title. The words are in all caps! How could PlayStation possibly compete with that?

Well, they tried

http://kotaku.com/193273/playstation-3-no-dummy-its-playstation-3?tag=gamingtop

It's official name was PLAYSTATION 3!!!!!1!!one!!!

Haven't read anything but the title (When I do that, I'm man enough to admit it) but I'm going to say that the Playstation brand is still the bigger brand. Sometimes, it seems like Sony is doing all it can to diminish that but the Playstation logo, the sound effect from the PS commercials, and calling all video games "Playstation" regardless of who the publisher is--that's just something the Xbox brand doesn't have.

The only reason the Xbox brand is putting up such a fight is because of poor choices from Sony.

PLaystation has more letters. 

In North America the XBox brand without question has overtaken the Playstation brand.

XBox is now "the" defacto brand, it's the HD market leader here, and it's the brand people most closely associate with big third party titles like Call of Duty.

Also Microsoft has successfully basically stripped Sony of every major third party exclusive (Final Fantasy, Metal Gear, Devil May Cry, etc.), basically watering down their brand importance.

Even nowadays when old people say "Oh little Johnny is playing his Playstation" ten years, now that has become "little Johnny is playing his XBox" in the US IMO.

I hear "XBox" being used more as a ubiqitious term for gaming in general moreso. Playstation is "old news".

I still say "Nintendo".

Ironically, I have a feeling Microsoft will start (or already has started) to feel uncomfortable with the name Xbox. The name, not the brand.

Just like Sony with Playstation, as you can see with PSN => SEN.

For search trends, Xbox is on top atm

Embedding doesn't work, the old fashioned way then

Playstation is still bigger when you consider its history. Even if you didn't...those Facebook likes speak for themselves.

EDIT: Although looking at those Google search insights, it tells a different story.

Playstation still has the edge pretty much all around the world. The only place X-Box has a slight edge is the US.