Is the 6d the same camera as the 5d mk II?

It looks like the Full frame version of what Canon did with the 60D vs. the 50D, which was a half step down from the 50D in some respects and a half step up in others.

Better ISO range and low light performance. Slightly faster handling, at least in initial fps. No word yet how using SD instead of CF will affect buffer depth (in theory the fastest SD write speed is slower than the fastest CF write speed).

Smaller & lighter body, but composite instead of magnesium. 100K shutter instead of 150K on the 5DII. More portable, less durable.

Improved and more various auto/scene modes. One less User definable "C" mode (2 instead of 3). The Digic 5+ processor is 3x faster than the Digic 5 and 17x faster than the Digic IV in the 5DII. This extra processing power can be harnessed to get better in camera jpeg processing as well as improve the accuracy of metering and better overall results in the auto/scene modes.

My take, until the camera is actually released and tested by independent reviewers, is that the 6D is more like a Full Frame "Rebel" than a continuation of the 5D and 5DII line. But just as the current Rebels exceed the 50D and even early 1D series in some respects, the 6D has 4 years newer technology in the sensor and processor than the 5DII. If you truly want to upgrade from a 5DII to the current technology, you must fork over the cost of the 5D mkIII.

5Dii (that I have) and 6D seem about the same.   Overall; I'd rather have the 6D.   They did "consumerize" a few things that matter but I'd trade those few items for the improved AF.

6D is a good match for Nikon D600.  I'm a bit ticked that Canon still sticks to the no-pop-up on FF mentality.  I mean; they added scene modes but not a pop-up?  Decide already; what pro or even serious amateur wants scene-mode-clutter; while many would find pop-up handy - particularly for fill-flash and remote control features (both perfectly legit uses of pop-up in any situation, no quality degrade vs. hot-shoe-external flash).

Pros

- AF is likely much improved (bigger, more sensitive, 11 vs 9).

- Improved high-ISO performance.  5Dii is very good already.

- Video will be more accessible, rather than digging through the menu.

- vastly improved metering.

- GPS *aaaand* WiFi.  Both have huge potential but most will never use.

- Digic 5+ vs. Digic 4 processor.

- Metering mode adds Partial.  Both have Multi, center-weighted, and spot.

- Slightly improved continuous drive.

- much expanded AE bracketing.   +-3EV vs. +-2EV.

- much expanded WB bracketing.  Like anyone ever uses this?

Cons

- 97% rather than 98% viewfinder. 

- 1/4000 vs. 1/8000 max shutter speed.

- Flash sync only 1/180 vs. 1/250.

- Mono vs. Sterio microphone.  (note: 5Diii downgraded to mono too)

- SD cards.

- Sad they didn't up to USB 3.0

- Noticably smaller / lighter.  A plus for some.

The 6D is meant to be a 5D Mark II REPLACEMENT. Not an upgrade. More of an update. 

AF points have increased from 9 to 11(thought the 5D II had 6 "invisible" af assist points to help with motion tracking). Still only 1 cross-type AF point.

Metering has gone from 35 zones to 63 zones with focus, color, and luminance evaluation. 

The 6D goes back to SD cards (and variants), where the 5Dii had a CF slot. A big minus for me.

6D sees a minor upgrade from the 5D II's 3.9 frames per second up to 4.5. This is an almost unnoticeable increase.

The 6D also includes a GPS/WIFI radios if that is your thing.

I wouldn't see the weather sealing a major factor, unless you plan on shooting in the arctic or the tropic AND have weather sealed lenses AND never plan on swapping lenses in those enviroments.

I like to think of the 6D/5D Mark II class as a "Rebel with a full frame sensor", if you will. The 6D is comparable to a T3i with the full frame advantage. 

No its not...6D will win HDR and ISO ..

The 6d is an upgrade from the 60d. The 5d mk III is the upgrade from the 5d mk II. It is the smaller body from the 60d series.

Seems so, improved a little but mostly a reduced version of 5D Mk II