Sony handhelds: always the bridesmaid
Nintendo has cornered the market on handhelds - they did it first, and they did it best. No one really cared about the PSP, let's face it; so why would they care about a smaller, UMD-less PSP? Sony's a great company, but they should really just stick with home consoles.
Besides brand familiarity and nostalgia, a large reason Nintendo's been so successful with handhelds is because (up until the 3DS at least), they offered a relatively streamlined, simple design. They left out all the bells and whistles in favor of charming, usually story-driven games that didn't take themselves too seriously nor bog down the player - Pokemon, Phoenix Wright, Professor Layton - heck, even Elite Beat Agents. Cheesiness be damned, that game was fun - and if you didn't think so, clearly you're a communist who hates music and all forms of happiness ranging from peaceful contentedness all the way up to blatant ecstasy.
In short, Nintendo developed, published, and simply provided a platform for games that played almost like books. And even after the 3DS' launch we still see games that play like books; books with smaller print and a larger need for reading glasses if you wish to avoid headaches, but books nonetheless.
Sony tried to take the other route, and neglected what consumers really wanted - they gave us bells, they gave us whistles, and they even gave us a few thingamabobs. But I don't want thingamabobs in my handheld game systems. There's just no room for them; if I'm sitting on public transport sandwiched between the gentleman overflowing into my seat and the lady wearing too much perfume, I'm not about to go waving my arms about to try to use motion controls, nor contort my hands to try and fire off a combo involving mashing eight buttons at once and swiveling one of the joysticks.
While you're sitting on the subway, the bus, the trolley, the backseat of a car from whose driver you hitched a ride, or in a seat on whatever form of public transport your local government is so gracious as to provide, you want a book. Simple and earnest entertainment that you can pause once you arrive at your destination.
To be perfectly honest, Sony's marketing tactics for the PS Vita are hinged on a rather cavalier attitude toward things like crossing the street and strolling down the sidewalk six inches from the curb as a speeding bus races by.
"Never Stop Playing"? Thanks, but I think I actually will Stop Playing(TM) and look up from my "3G gaming" experience so the bloke with the earring doesn't go home and blog about the pile of guts that was left on the sidewalk after some punk couldn't pause Lego Harry Potter: Years 5-7 long enough to look up for a second before he stepped off the sidewalk into the path of the Route B North.