Looks like it has a couple more HDMI inputs and one more output. To me that's a meh, as most people would not have 8x HDMI inputs anyways in one room :P
However, it does offer HDMI 4K upscaling, so if you have or plan to have a 4K TV you might get value there. It also pushes a little more wattage per channel 165W (700 series) versus 185W(900 series). Both are 7.2 channel.
If that 900 series is still in your budget, it's a tad better receiver for sure. If you plan to have a 4K TV at some point with this receiver, then it's a for sure I'd guess. I mean you can never go wrong with a little more wattage per channel either.
I have Pioneer Elite and Denon and I love both! I have been running a professional series denon in my home theater room for about a month now and it's pretty solid, so I would buy Denon again for sure.