At least, that's the only conclusion I can come up with. Apple produces sexy devices like the iPod and iPhone, devices that â'' for the most part â'' do things you have always wanted these devices to do. The iPod finally gave MP3 players their distinction from other audio devices, by storing 50x the music other kinds of portable audio players could, and doing it in a beautiful device with a beautiful user interface. The iPhone is the first music phone that doesn't compromise on either the music player or the phone, and gives most folks most of what they would want out of a smartphone, in a beautiful device with a beautiful user interface.
I've never worked at Sony. It has been a long time since I've developed a game for a Sony platform. So I don't have a store of insider knowledge about how things go with Sony. But I own all the Playstations, a PSP, a Sony Reader, I have a couple of old Minidisc players in the basement (I believe I said I was a gadget freak), and I've roamed trade show floors and tech conferences for years, so I think I have a decent enough view of why Sony fails where Apple succeeds.
Apple has chosen to make devices that improve the experience people are having with things they already deal with. Sony is making devices that also make you adopt some class of technology that you didn't have before (on the assumption that this new tech is better than what you already have). So while Apple gave you a way to take your MP3 library with you, Sony DAPs made you convert your music to their ATRAC format, and put it on their MemoryStick or Minidisc media. Not that ATRAC, MemorySticks, or Minidiscs are bad, but no one had them, and thus no reason to have devices that use them.
No one has a plethora of Blu-Ray discs hanging around, in need of a player, so the fact that the PS3 plays Blu-Ray discs is nice, but not urgently so. No one had a pile of UMD movie discs hanging around, saying to themselves, "If only I had a portable player for these." eBooks are not such a big market that people are searching for that perfect ebook reader, even though Sony has pretty much produced one. Sony produces sexy devices, but as part of a family of formats and content, wanting you to embrace all of it, so they can get all of your dollars.
Sony's stuff is expensive, but so is Apple's. That's not the reason for lukewarm acceptance. Apple sees the potential of their products from the user perspective, and delivers on it. Sony sees the potential of their products from the corporate behemoth perspective, and delivers on that, and everyone can see the difference.