bran wargs into hodor, and hodor/bran breaks free and helps bran, jojen and meera escape before jon shows up. that way they never meet as in the books.

although the preview showed jon et al attacking those at crasters keep, so hodor can't do too much damage (would be nice to see him wreck ****!).

i agree we need to see more warging. definitely been glossed over in the show compared to the books.