More details are emerging about Apple's forthcoming watch, which is targeted for release this year, according to a Bloomberg report this morning and corroborated by our sources. Bloomberg says the watch project has long been a favorite of Apple design chief Jony Ive, who reportedly ordered "boxes" of Nike sports watches for his team to study a few years ago.

That's perfectly in line with what we've heard about the watch project, which we're told is being led by Ive himself with some 100 engineers under him. Interestingly, we're also told that Apple's chosen to rework the full iOS to run on the watch instead of building up the iPod nano's proprietary touch operating system — although the previous nano was already watch-sized and seemed like a great starting point for a wrist-sized device, Apple's betting on iOS across product lines.

Apple's betting on iOS, but battery life is a challenge

That's apparently leading to battery life issues in development, according to our sources: the goal is to last at least 4-5 days between charges, but the current watch prototypes are apparently only going for a couple days max. We're also told Apple has some work to do with iOS on the iPhone, which currently has several hooks for supporting a watch-like device but lacks the appropriate interface or settings to make it work properly. The Pebble watch, for example, can receive notifications from third-party iOS apps with a slight hack, but it has to be redone every time the Bluetooth connection breaks.

Investors are starting to latch onto the watch as TV rumors fade

Obviously Apple has time to resolve these issues, just as it had to when it reworked OS X to work on the iPhone instead of building up the iPod's operating system in the late 2000s. And it should be motivated to resolve these problems quickly: financial analysts are already starting to latch onto watch rumors as a growth opportunity for Apple's battered stock price since the fabled TV project looks increasingly unlikely in the current media climate. (That Bloomberg report is headlined "Apple's Planned 'iWatch' Could Be More Profitable Than TV," in case any investors missed the underlying subtlety.) And Google is promising that its high-concept Glass wearable device will be out this year, lending momentum to a market segment that's remained essentially untapped for years but which has flared to life as indie projects like the Pebble, MetaWatch, and others find success with early adopters.

We're actively digging for more info — we'll let you know more as we hear it.