Maitreya (Mi-le Fo) is the next buddha, after Shakyamuni Buddha, who is currently living in the Tushita Heaven, but who manifests from time to time to teach living beings. Based on his vows and merit, he will transform this earthly realm into a world of saints similar to the “Western Paradise of Ultimate Bliss.” Living beings who have a karmic connection with him will become his citizens, see this Buddha, hear the dharma, and attain enlightenment. Name literally means The Loving One. His Holiness Wan Ko Yeshe Norbu has told us that originally Maitreya was to achieve buddhahood before Shakyamuni Buddha. However, Shakyamuni stayed to listen to a discourse being given by Dipankara Buddha that Maitreya felt he already understood. Because of the insight and merit gained from that one event,Shakyamuni Buddha became the current Buddha. This is how important it is to listen to discourses and read Dharma books, even when you may think you are pretty advanced. See Receiving Dharma.
Bodhisattva’s birthday is celebrated on or near the first day of the first lunar month each year.
Dharma King Trulshik Rinpoche of the Nyingma Sect was a current incarnation of Maitreya Bodhisattva.