Define failure please. I'm sure Sony's not lighting any cigars back at HQ over the Vita's opening month of sales but at the same time they did sell out of the initial shipment and have yet to have the worldwide launch. All you can really say at this point is that the Vita is not performing as well as the 3DS or PSP in Japan and make a prediction based on upcoming releases and the limited knowledge that we have.
People here keep saying they expected the Vita to come out of the gate far stronger because of the holiday season but I really don't think that applies in this case. Past history is only one piece of the puzzle when predicting performance but in today's changing market it needs to be taken with a giant grain of salt or not at all. Given that the PSP is still very healthy and that the 3DS had a stellar trio of releases in the period and looking at the Vita's launch titles and pricepoint I think that the Vita's performance is pretty much expected. In short, I don't imagine Sony is much surprised or in panic mode over the Vita's Japanese performance. There's no failure here yet.
I think that the worldwide launch is going to be interesting and the spacing of software releases for the Vita as well as any new announcements will help paint a picture of the platform's early health. I also think that Sony isn't as reliant on the Vita's market penetration as Nintendo is with the 3DS. Nintendo absolutely
had to get the 3DS in tip top shape in 2011 because that platform has to carry the load for Nintendo this year. Sony at least has the luxury of a platform that's finally making money with the PS3 and is probably content to let the Vita do what it will do for at least a year before any drastic action is required.
Of course I'm not saying that Sony shouldn't have done whatever was required to get MonHun exclusivity for the Vita or that the 3DS isn't currently trouncing the Vita's sales in Japan because both of those are true statements. But let's at least get a year or so of worldwide sales numbers under our belts next time before we start calling a certain system a failure.