The Rose Bowl "tie-in with the Big 10 has been around for a very long time (tradition/money you know). Not so suddenly, it isn't the the "Big Daddy" of the bowl games anymore with the BCS championship game with all the "hoopla" still to come.
That, along with the fact that the Big Ten Champion isn't necessarily a national power with a lofty ranking leaves for nothing more than a great parade and a decent New Years Day football game at best.
It still is a great "treat" for the boys from the Midwest to go to Southern California, during the height of winter, and play a football game (ho-hum for the California boys).