Upload & Sell: Off
I'm currently shooting a 5D2 and a 7D. 95% of my photography is landscape stuff, and compared to the 5D2, the 7D just doesn't cut it. I was going to buy a 5D3, but the 6D looks like an excellent alternative. Significant savings, and some really cool features like WiFi and GPS. The .9 MP decrease doesn't really concern me at all. I am hoping that the overall DR has gone up with the all new sensor though.
Overall I'm excited, and the big savings over the 5D3 means I'm that much closer to adding the new 24-70 2.8!!!
If you're serious about landscape shooting and you want to add an inexpensive new body, you owe it to yourself to look at the D600. From what I've seen so far (have not used one) it looks like the DR is impressive and once again exceeds Canon's capabilities, it's a more full featured camera compared to a 6d in most other ways, and will do more for the end result.
Sure you'd need to add another lens or two, but if the images can yield better IQ after adjustment, then it makes a lot of sense.
Not just another lens or two, another GOOD/GREAT lens or two. No point using a good camera if you don't pair it with a good lens. Thing is, that usually translates to "very expensive".
I started buying Nikon mount landscape lenses for my Canon cameras a couple of years ago. Inexpensive superb primes like the Cosina Voigtlander 58 mm and 90 mm SL II lenses. Best lens investment ever.