Guys don't get too exited please.
It's not going to be a big redesign; most likely:
-same chassis, slightly thinner and lighter
-color options
-same screen sizes
-same ports, except TB2 replaced with TB3/USB-C, still 2 USB-A ports, MagSafe 2, headphone/mic jack, and Hdmi (if we are lucky we might get hdmi 2.0)
-processor update to Skylake/ 15" gets AMD Polaris GPU
-claim of all day battery life for the rMBP
And that's it.
No redesign, no port cutting.
Redesign with full USB-C is probably coming with the late 2016 ones.
Apple never delivers every new thing in one iteration. They are going to upgrade it little by little, so the consumers get the feeling of at least some upgrades made to the products.
Haven't you learned anything in all those years!