Apple's next iPhone is...not yet in production
BGR

Rumors today, contrary to recent reports, suggest that Apple has not yet started the final production of its next iPhone. Instead, the handset is said to be in the third phase of its engineering verification tests and still needing pass through design verification tests before making its way to the assembly line.

What You Need To Know:

- It's believed the next iPhone is on track for a Fall 2012 release.

- Apple is said to be testing units that have 1GB of RAM and 4G LTE support.

- It could also support NFC hardware, enabling mobile payments.

- The next iPhone is rumored to be slightly taller than the iPhone 4S and feature a 4-inch display.

Other sources

Who knows, maybe we’ll get lucky and some engineer will leave a prototype laying around, again. - Charles West, Into Mobile  
So what we’ve learned from this report is the next iPhone…isn’t ready yet. - Gary Ng, iPhone in Canada  
BGR
New iPhone on track for fall release, 4G LTE and NFC confirmed, final production starts later this summer  

...we have confirmation that the units Apple is currently testing have 1GB of RAM, doubled from the iPhone 4S’s 512MB, and integrated 4G LTE radios. We can also confirm that NFC hardware is present in the phones as well

iPhone In Canada Blog
Rumour: ‘iPhone 5′ Has 1GB RAM, LTE, NFC, Still in ‘Engineering Verification Test’ Phase
Phone Arena
New iPhone rumor confirms 4G LTE connectivity, double the RAM and a built-in NFC chip
Mobile Syrup
Rumour: New iPhone coming with LTE, NFC and double the RAM
Electronista
Next-gen iPhone expected to get NFC, LTE, 1GB of RAM  

The next-generation iPhone will have 1GB of RAM, LTE 4G, and most notably NFC hardware...

Other
iPhone 5 to have 4G LTE and NFC, double the RAM of its predecessor. Production hasn’t started yet  

Contrary to the latest report we heard on the matter, apparently production for Apple’s next iPhone hasn’t started yet.

iPhone Hacks
‘iPhone 5′ With 1GB RAM, 4G LTE And NFC On Track For Fall Release  

Last week a report claimed that ‘iPhone 5‘ had hit production and had speculated that it could be released as early as September. However, folks at BGR claim that according to a trusted source, the next generation iPhone is still in engineering testing stage and yet to enter production, but is on track for fall release.

Into Mobile
Another rumor claims the new iPhone is on track for the Fall, LTE and NFC a go