kingpotnoodle
Given that this appears to be all about mobile let me be the first to wager that what they actually mean is the Pentium and Celeron brands moving to cover higher-end SKUs in mobile devices rather than the Silvermont cores moving upwards to replace them in the desktop market.
Did you read the source Anandtech article? They show ITX desktop motherboards at the end, Celeron branded.
Atom is a tarnished brand, I don't know anyone that liked the old ones. Looks like this time they did a better job, makes sense to sell them as Celeron, and hope everyone forgets Atom.