Several years ago, I decided that my only practical response to the gadget industry’s unreasonable rate of obsolescence was to impose unreasonable purchase requirements of my own. That is, once I’d gotten comfortable with a phone, computer or other device, I would insist that its replacement vastly exceed its performance in a few significant ways–this way, I might wait longer to upgrade, but then I’d feel vaguely like I’d won.

I bought my current digital camera back in the summer of 2007, and by the usual camera metrics I’m clear to upgrade: I can easily get double the zoom lens as well as wide-angle capability, doubt the resolution, faster shot-to-shot performance, smart picture modes like automated panorama generation, and high-definition video recording with stereo sound. And this next camera would also be thinner than my current model (even if it probably wouldn’t take AA batteries).

Unfortunately, the camera on my phone–while inferior to my four-year-old “real” camera in every measure of picture quality–also geotags photos automatically and allows for near-instant sharing on Twitter, Facebook, Google+ and any other online service with a phone-friendly site or app.

All this is to make clear my ulterior motive in trying out a round of cameras over the past few months, as written up for Discovery News on Monday. I’d hoped that a clear winner would emerge among the four models I tried there, three with built-in GPS–Canon’s PowerShot SX230 HS, Panasonic’s Lumix DMC-ZS10 and Casio’s Exilim EX-H20G–and one that borrows geotagging from a nearby Android phone, Samsung’s SH100.

(I also tried a fifth model, Nikon’s 36x ultrazoom P500, but wound up only having room to mention it in passing in the Discovery piece.)

No such luck. The Canon and the Panasonic ruled themselves out for sluggish GPS performance or bad battery life, while the conceptually-impressive Samsung flunked for its clumsy, expensive system of pairing with too-few Android phones. If I had to buy a phone among this bunch today, the Casio would be the likeliest to land on my credit-card bill–but I’m annoyed by the fact that I can’t recharge its battery by plugging the camera into a computer’s USB port or any other USB charger, much less the fact that Casio still seems to think it’s okay to use a proprietary USB plug in the year 2011.

But I’d also worry, given the average useful life of a camera, that in a year or so, we might finally see the camera-to-phone fusion prototyped in the Samsung done right. (Hint: Use Bluetooth instead of WiFi to avoid making the user pay for tethering on the phone.) So it’s easier for me to wait and limp along with my four-year-old model–which, aside from its eroding battery life, continues to take decent pictures. How much longer do you think I’ll be doing that? Any other cameras I should consider?