Disclaimer: I am a huge Sony fan, I used to own a PS1 and a PSP and I still own and love the PS2 and PS3, so this is not a fanboy argument.
The release of Sony's PS Vita is nearly upon us and I'm going to stick my neck out and say right now that it's going to fail. It's already flopped in its native country which, although doesn't mean it can't do well here, doesn't exactly bode well for its chances. The reason I believe it will fail is simply because Sony have made far too many mistakes.
For starters the console and it's accessories are far too expensive. To buy the cheapest version of the console and a memory card costs more than to buy a brand new 160GB PS3, thats just plain wrong. A handheld should never cost more than its home console (admittedly the 3DS is more expensive than the Wii). Although some shops offer bundles that include a memory card, many do not and it is simply too expensive to buy everything you need to use the console properly.
Secondly instead of handling PSP back compatibility properly and making it total, they have limited it to the titles that they post on the PS store which, although they say they will update, they may very well not - they aren't overly great at updating the PS1 or PS2 section are they?
On top of all this one of the main parts of the console, it's touch functions, seems utterly pointless. The only purpose it seems to serve in most games is small and gimmicky at best, there is no real need for it. Why add things on that don't need to be there and make handling the console more awkward than it needs to be? Sure on many of the games for the 3DS the 3D effect is only a gimmick but on games such as Super Mario 3D Land it serves a real game changing purpose that is more than just a charcoal rubbing gimmick (for those who don't know, Uncharted: Golden Abyss makes heavy use of the touch effects for charcoal rubbing).
Many say that the launch line up redeems all of its failings but does it really? Have you seen the line up? There are a few blockbuster titles like Uncharted and Fifa but as its a Playstation handheld I'd have liked to seen Resistance, Killzone, Infamous or Metal Gear up there as well. Instead the rest of the impressively large line up of launch game seems to be populated by average to good games that aren't really anything special. It's not even as if these other key games are on the horizon, Resistance drops I. may and the MGS HD collection is on its way but there is seemingly no Killzone or Infamous and no new MGS. To add insult to injury the current blockbusters aren't even up to the standard we have come to expect from them.
Ultimately, as a Sony fan, it's sad to watch the PS Vita, the nearer we get to launch the happier I become that I bought a 3DS.