Just thought I'd note that I was able to install Dreamweaver CC and Photoshop CC on the same machine that I already have DW CS6 and PS CS6 installed. (under windows 7 ). It doesn't seem to be an issue. So, if you have enough room, it appears you can run them both on the same machine.
I am only doing this on my desktop. Leaving CS6 running on my Laptop for the time being.