I hope you folks that said Gelbvieh are correct since we raise em.
I think many larger commercial producers are starting to look at structured crossbreeding programs, comparable to what the swine industry has been doing for 20+ years. In the swine industry they use specific breeds/hybrids for the maternal (i.e. Yorks and Landrace) and terminal (Durocs and Hamps) sides of the equation.
So, in the beef industry producers will use specific crossbred cows:
-in the higher rainfall areas (Midwest & upper southeast) they'll use SimAngus or Balancers
-in the south it may be a Tigerstripe, Angus/Brahma F1, etc.
-and in the lower rainfall areas (OK, CO, WY, etc.) it may be a black or red baldy.
On the terminal side they'll use high growth, muscular bulls. Consequently, I think Charolais will gain much of this market. And for producers who are wanting black calves they'll use high growth, black Limmy's, Simmy's, Gelbviehs, or Chi bulls.