Dude I was just about to post this. I haven't been this excited for a new tech release for a while. The Core 2 series was the last, but it's nothing compared to the Jordan game 6 AMD is pulling, which is nothing short of incredible. The CPU industry really needed better competition. Intel's pricing was getting insanely outrageous. Also f*ck Intel because they are dodgy as f*ck and I've stopped buying anything from them.
For those who haven't watched the video, AMD's upcoming Ryzen desktop CPUs (Q1 2017) running on the AM4 socket with DDR4 RAM will be outperforming the top Intel offerings at a significantly lower price. So hold off your purchases.
Btw, this benchmark by AMD has been replicated and found to be plausible.
I wouldn't worry about upgrade path, AMD has always had better upgrade paths than Intel. It's always a smooth transition. At the same time though, with how different the Ryzen chips are to the Bulldozers and Piledriver AM3+ chips, I wouldn't be surprised if an entirely new chipset is needed.
The only qualm I have with this is the lack of quad channel memory support. While there isn't a huge gain in performance from the jump to quad channel from dual channel, I still feel it will increase the performance advantage AMD has over Intel at launch and possibly extend its advantage for longer which would give them more time to better the next revision.
Also SenseMI is giving me a nerdgasm. f*cking cool as hell.