The archetypes will continue to change.
The fact is, they have to change for the following reason:
TRIPS
Regionals didn't give out trips. This year, trips are harder to come by. If Regionals gave us new decks (mewtric, flariados), you can bet your boots GCs will too, because trips are on the line. Players will have new and awesome decks to bust out for the GCs, and they'll win- and the metagame will once again shift during GCs and for Nationals.
It's also interesting to see the disparity in regionalities for the US. West, Midwest, East, Southeast all have very, very different metagames. Entire archetypes are non-existent almost.
Rocklock, at least in the east/southeast is 100% dead. I know it's played in the west a little, and perhaps a tiny bit in the midwest.