While the PS Vita launched to a great start in Japan, shifting around 325,000 units in its debut week, post-launch sales haven’t kept up the momentum. In fact, during the past week in Japan, the Vita fell below 3DS and even PSP numbers by a significant margin. However, Sony Computer Entertainment America marketing guru John Koller says the sales are still tracking in line with expectations, and wouldn’t take them as an indication to how the handheld will perform stateside.

“If you look at the word-of-mouth factor, it’s really strong because people are bringing it home and really enjoying it,” he said. “That satisfaction rate is really high. But also in terms of when we funnel in additional hardware units, that’ll dictate how many sales there are and how many sell through,” Koller told GameSpot.

“One of the things we have learnt over a long period of time, is that whether it is PS1, PS2, PSP or PS3, it is dangerous to the point of impossible to take any experience from the Japanese market and try and extrapolate it, and propose upon what will happen in Europe or North America.”

Further, Koller shifted attention to the steady stream of software titles due out for the Vita. With AAA franchises like Mortal Kombat, Resistance, Little Big Planet, Call of Duty, and Assassin’s Creed slated to release in the “subsequent months” following launch, Sony hopes to mitigate the post-launch lull that usually plagues new hardware launches.

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