Note that in the article it says that the MSI laptop with the desktop 980 GPU will have a 230W or 240W AC adapter. That isn't good enough. It needs 240W for the mobile 980m and moderately powerful Haswell/Broadwell/Skylake chips up to extreme unlocked CPUs. 180W causes throttling (which MSI and Alienware have learned the hard way).
These laptops with the desktop 980 GPU will need a ~330w AC adapter or whatever the next size up is from 240w. I wonder how much heavier they may be from more heatsinking and if they'll all switch over to 12V fans rather than 5 volts, like MSI has been doing for a few years now.
I just ordered an Alienware with 980M, 4k display, and the 6820HK mentioned in this article. Should I cancel and hold out for one of these newer models with desktop 980?
I'd cancel. Maybe even if the laptops with the desktop 980 GPU aren't too your liking, the model you are interested in already will be less expensive.