According to Phil Ewaniuk at Official PlayStation Magazine UK, The Witcher 3 is “big,” and “beautiful,” but not a true open-world. Describing the environment in the game, Iwaniuk said it is “a big one, yes. A beautiful one. But not open, and certainly not a sandbox in the way Skyrim’s environment operated.”
While fans of RPGs like Skyrim were hoping for basically the same idea, but bigger, the early impression Iwaniuk got did not match this expectation. “As Dragonborn, you could disappear for months ascending the ranks of various guilds, getting married, buying property and clearing dungeons while everyone waited patiently for you to save the realm,” Iwaniuk writes. “As Geralt though, you’re rarely able to shake off the grip of the developer’s hand as it guides you from point to point.”
He goes on to explain that many of the large areas in the game, such as Skellige and White Orchard, are accessible “but not in real time.” You cannot access them from Valen, the primary setting of the game – you can only fast-travel to them. This makes The Witcher 3: Wild Hunt definitely different from Skyrim, where you can travel around all of the game’s areas in a continuous route.
Despite the not-so-open world, however, early reviews of the game have been very favorable – some sites have even called it among the best games ever. We shall see as the release date of May 19th approaches!
Source: http://www.gamesradar.com/witcher-3-wild-hunt-review/opm/