Of course, premium cable shows which run without adverts have more time to spend on title sequences. Recently we saw Starz's Pillars of the Earth, which had a great title sequence with paintings coming to life and the cathedral rising out of the ground (this is the only link I could find, but weirdly it's been mirrored), but HBO generally has had some of the best title sequences recently: Rome with its graffiti coming to life as daily life in the city plays out around it; True Blood with its evocation of sex, religion and heat in Louisiana; The Wire with its scenes of life on the streets of Baltimore; and Carnivale's weird, surreal juxtaposition of darker moments from history with Tarot cards.
Obviously HBO were going to come up with something special for Game of Thrones and contracted Angus Wall and his company Elastic to do the job. Wall was the creator of Rome's title sequence, which won him a BAFTA, and also Carnivale's, which won him an Emmy. His work as an editor on The Social Network also won him an Oscar, so clearly he had the qualifications for the job. In an interview with the Hollywood Reporter, he explains that the title sequence was meant to evoke the maps found at the start of every Song of Ice and Fire novel (and fantasy books in general) and the mechanical innovation of a late-medieval society (not a primary theme of the novels, though such innovation is referenced in the maesters' Citadel and also the Free City of Myr, where great advances are being made in optics) whilst also fulfilling story-telling functions: the sequence subtly outlines the history of the Seven Kingdoms and will change several times a season as new locations come to the fore.
The conceit of the sequence is that there is an immense globe of the world, with the continents of Westeros and Essos outlined on the inner surface of the globe rather than the outer, with a sun at the heart of the sphere ringed by a mechanical astrolabe. The whole thing is similar to a miniature Dyson Sphere. Under the surface there are gears, cogs and pulleys which, when activated when the camera gets near to particular locations, allows buildings and features to rise up out of the surface of the map. In the first episode, the cities of Kings Landing and Pentos, the castle of Winterfell and the Wall all rise up out of the map, with individual buildings and locations (such as the Red Keep and the Great Sept of Baelor in King's Landing, and the godswood in Winterfell) easily visible.
These locations will change as the series progresses: Pentos disappears from the sequence in Episode 2 to be replaced by Vaes Dothrak, whilst the Twins and the Eyrie will join the sequence in later episodes. With Season 2 confirmed, I'd expect to see Dragonstone, Pyke, Storm's End, Riverrun and Qarth appearing on the map.
A very nice touch is that the astrolabe surrounding the sun has scenes from the history of Westeros chiselled into the side of it. We see three such scenes during the title sequence: at the very beginning and end, and just after the camera visits Winterfell. In the first sequence we see a volcanic eruption destroying a city whilst a dragon looks on and people flee by boat, a clear depiction of the Doom of Valyria and the flight of the Targaryens to Westeros (technically the Targaryens didn't flee the Doom directly to Dragonstone, they were already there manning a trading outpost with the Seven Kingdoms, but that doesn't sound as cool). In the second the dragon is being brought down and killed by a direwolf, a lion and a stag, a reference to the alliance between the houses of Stark, Lannister and Baratheon that removed the Targaryens from power. The final scene has the other animals bowing down to the triumphant stag, noting that the Baratheons now hold the Iron Throne.
We then get the final logo for the series, backed by a great sigil showing the heads of the Targaryen, Baratheon, Stark and Lannister heraldic animals and setting out what the principle factions in the game of thrones will be.
It's a great title sequence. Some elements are odd - the 3D map, the Dyson Sphere-like set-up and the mechanical gears seem too advanced for the setting - but it also does a great job of showing the various locations and hinting at the deeper backstory behind events. Ramin Djawadi's theme tune is also a bit underwhelming at the start, but it's growing on me every time I hear it. HBO have poured a lot of effort into this - Wall apparently worked on the sequence for over a year - and the results are impressive.