Phones, the uber gadget, and dedicated devices

When I go to work it is not uncommon for me to carry my phone, music player, netbook, and iPad; there's never a guarantee that each item will be used that day, but I can't see myself not having each of those items with me. It's not that I couldn't boil that down to two items: the phone and the netbook. It's that I don't want to.
The modern phone is an amazing thing, blending telecommunications usefullness with a smattering of computing utility. I can listen to, and download anywhere, podcasts, music, and video on the phone. But I don't. No, instead of plugging into my 4.3" slab of glass and Android, I plug into my 3 year old white OG Zune. Why? Because it's perfect for what I want.
With the Zune I have a dedicated device optimized for listening and watching content. It has hardware buttons that can be accessed without going through a lock screen, volume that can be adjusted through a pants pocket, and an interface that is designed to do one thing: play shit.
So I find myself very rarely using the much more technologically advanced phone to listen to anything, and I still go through the nightly sync cycle that ensures I have an up to date selection.
My specific situation isn't the only example of a dedicated device that seemingly makes no sense in this modern world. Take the Kindle, a single function devices that is seemingly usurped by the iPad, the do-almost-all ubergadget that I'm typing on right now. While the Kindle can be used to read books, the iPad can be used to read books, write books, watch the movie based off of the book, and play the mobile video-game spinoff of the book. But the iPad isn't perfect. It's too heavy for extended reading sessions, it's display is more tiring to look at than e-ink, and the interface is designed for general computing, but dedicated reading. From a value standpoint the Kindle seems to make little sense (and much less sense when it cost 50% of the iPad), but for usability it's unbeaten.
So now we find ourselves at an odd nexus; increasingly capable and impressive machines that do everything, and increasingly cheaper and better machines that do a single thing, and do it well. While many pundits have called each new ubergadget the killer of this, and the killer of that it's becoming increasingly obvious that single purpose devices are going to continue living on. What the ubergadget is killing, however, are the middling and poorly designed single purpose devices that end up cluttering junk drawers across the country. And that's a good thing.