My personal belief is it's not likely to happen, but considering all the twists story-&-plot-wise this season had, I suppose they will at least imply they'll be together in the future, adding some reference to the japanese legend of the red string of fate if the Anime
department decides to continue the series with all the financial problems OLM & The Pokemon
Company Japan are actually having.
Although the commong thinking is tending to believe this will be Ash's final saga, cuz Pokemon Anime Production & licensing in Japan has suffered several budget cuts because of the anime popularity breakdown in japan (this means... actualy AniPoke merchandising has very low sales compared to Diamond & Pearl Cycle & Best Wishes pre "11-M-2011 earthquake-plot-twist" period, All Nippon Airlines closed all flights with the Boeing 747-400 Jumbo Pikachu cause of present low rentability & ambiental-technology issues. The new movie is gonna be more short-length than "Mewtwo vs Genesect" cause the budget cut & Pokemon Get TV, the variety show is being made in a more humble & cramped studio compared to former Pokemon Smash Variety Show). If this thing happens, it would be no suprise the Anime department decided to make Ash more badass, giving him a childhood friend & implied love interest turning to "Victorious Childhood friend" in the future (according to TVTropes) and make some "love plots" to develop this relationship (as viewed into eps. 5-6-7. Also, it was confirmed today in CoroCoro that Ep. 12 in Japan will be a "Date & Jealous episode" where the Nymphia trainer threatened Ash to date her if her Nymphia beats her Keromatsu in a battle).