The only reason "analysts" are predicting an early 2015 release is because they have heard literally nothing about the device.
Some schematics and mockups of the iPhone 6 have been around, but no one will come out and verify any of them as being exactly the same as what the final product will look like.
Otherwise, leaks have been at a minimum this year, and speculation has therefore been all over the place. Sapphire! No sapphire! 5.5 inch phone! No, display issues. No, battery issues. Nope, no 5.5 inch phone! Wait, yes, 5.5 inch phone, but next year (because, again, no info)!
Point is, just because these analysts don't know anything doesn't mean that we won't see the iWatch until next year.