I've got a 2012 15" rMBP, and I love it. It's currently going strong so I can't imagine I'll be replacing it with a new model soon, especially not since they've removed most of the ports I use daily! I'm not happy about only having USB-C on the new model - I'm a musician, producer and animator, and find I carry enough adapters and cabling around as it is to record bands and perform, I really don't want to carry more, nor can I afford to replace all of my audio peripherals, as much as a thunderbolt recording interface is tempting. Also, losing the magsafe connection was a foolish decision - bordering on contemptuous of their users - it's saved my Mac more times than I can count and is easily one of the best design features of the macbook. Knowing Apple, that's exactly the point though eh!? Probably realised they could be milking pro users even more if they were only knocking their macbooks off more tables and damaging more cables. As much as I want more graphics power and processing power, the connectivity on my 2012 rMBP absolutely destroys that available on this new model, both in terms of flexibility and number of connections at any given time. So no new macbook for me, at least not soon, or if Im paying for it!
That said, I'm extremely keen to try one and play with the touchbar, and I wouldn't turn my nose up if someone gave me one! The extra performance will be probably be enough to tempt me in the end, once more of my setup has migrated to thunderbolt, and it is, as always, an utterly beautiful bit of kit.
Edit: Who am I kidding!? I've just looked at the differences in memory read/write speed, processor and graphics performance vs my mid 2012 rMBP, and the new one will prove to be miles faster than my 2012 model. OK, I definitely want it, but I can't afford it right now.