I watched the episode the other day and I completely forgot to tell you what happened. Well, Piplup fell in love with a Marill but there was also an Elekid that did too. Piplup, Marill, and Elekid all got captured by Team Rocket and it was basically Ash, Dawn, Brock, the COTD trying to find them.
We didn't really get a lot of Pearlshipping hints in the episode, unless you consider Ash worrying over Piplup more then Dawn was a hint.
Either way, this was a good episode.