Although Sony has already introduced the UMD-less PSP Go, they still plan to offer the PSP-3000 alongside the new unit, which means they're still committed to the UMD format.
This is a fact that Sony wishes to reinforce: UMD isn't going to fall by the wayside any time soon. According to a recent Develop interview with Sony Europe's Zeno Colaco, the PSP "probably has the best UMD lineup ever on PSP this year." Several blockbuster titles will arrive within the next month, and that includes both Gran Turismo PSP and LittleBigPlanet PSP , but don't forget about Tekken 6 , Grand Theft Auto: Chinatown Wars and MotorStorm: Arctic Edge . Said Colaco:
“I think the key thing is that we’re not moving away from UMD just because we’re making strides in digital distribution. From the beginning we’ve said we’re sticking to a two-SKU program that will sustain PSP and PSPgo. Most of our projected sales for this year are via UMD. We’ve already got strong support on the UMD-side, so it’s time we expanded further."
Let's not forget that many millions of people (about 30, currently) own one of the UMD iterations of the PSP, so it wouldn't make much sense for Sony to abandon the format entirely. Granted, they will likely switch over to all digital at some point, but it certainly won't be any time soon. This should appease all those who think their current portable model is suddenly out-of-date, and they won't be seeing any more games for it. Don't you worry, peeps.