Is it possible to keep using iPhoto after starting to use Photos?


Question: What is the price graph of Nikon cameras?
Answer: The price basically starts high and ends low. You can expect to pay full retail for a camera (or lens) when it's introduced. After demand is sated price drops a little. As the product gets closer to end of life, price will drop more.

I doubt that the price you pay for a D7100 will be the same as the price for a D7000 today. There's some discount on the D7000 already ("instant rebate") and I'm sure the D7100 will initially cost full retail price.

Will the price difference be worth it? Well, you'll only know that after the D7100 is announced. And the D7000 price may even drop more after the 7100 is announced. But then, I am betting that in 2014 a D7200 will be released, and in 2016... The D7000 is an awesome camera; don't get caught up in the waiting game!