While they are all in the diner for lunch, Christopher receives a call on his cell phone from Emily Gilmore. It seems awfully suspicious that Emily just happens to call Christopher when he is in Stars Hollow, and even more of a coincidence when it turns out that Emily knows his parents are in Connecticut at the same time.
Knowing Emily’s passion for meddling in Lorelai’s affairs, it seems likely that Christopher’s trip back east was engineered by Emily in the hopes that he would get closer to Rory, and maybe to Lorelai, and would bring Christopher’s parents, the Haydens, back into the fold as well.
It is Emily’s desire that Lorelai and Christopher form a family together with Rory, with the blessing of Straub and Francine Hayden, who haven’t bothered to see their granddaughter since she was a baby. This definitely looks like one of Emily’s master plans, and Richard’s comment about Christopher’s new business back in the Pilot show that the elder Gilmores had been in regular contact with Christopher for some time (and perhaps had always been).