It is difficult comparing it with ESPNs games as they were always on Saturday evenings, I am sure that if you look at BARB you will find tv audiences are always bigger for programmes in the evening than on Saturday early afternoons.
I dont think they will be too concerned, Rugby viewing figures are up over 100% on last season. As for English football, they are never going to topple sky in the first season. They have a good selection of foreign matches though.