Sony had planned to release a 'network centric' model of the PSP ever since the beginning, according to an interview on website GameBusiness.jp.
In an interview with the head of SCE's product planning division, Naoya Matsui, it has been revealed that the company was simply waiting for the digital pipeline to reach a mature-enough state to sustain such a device.
"We'd planned to release a PSP model without a UMD drive since the very beginning," says Matsui. "But if we'd simply released the hardware, there wouldn't have been much for everyone to enjoy. We needed to prepare the right environment for it first - things like the transferral of content with the PS3 and PSN, and PC software to manage content like music and movies such as 'Media Go'.
"We wanted to release it when the delivery of digital content was on par with the delivery of physical media. Thats what we've been working on these past two years. We'll be selling the PSPgo alongside the existing PSP models, because it's a product targeted at those people who are more accustomed to digital content."