Mikage passed the Tochigami Crest (the symbol of divinity and ownership of his temple) to Nanami, but obviously retained several of his powers.
Like when he converted Nanami's dress into a butterfly pattern before her ritual dance in the end of 1st season.
He is no longer a god, because
he did not attend the Izumo meeting in the second season.
and also because
the host god of the Izumo meeting [name pending] specifically states that Mikage is hard to find because he is no longer a god.
So, what is Mikage as of the Izumo meeting? He is not a god. Is he a youkai, a fallen deity, or what?
EDIT: In the episode S2E4 "The Goddess Makes Her Second Romantic Confession", Mikage is shown at the god's summit closing banquet. So he has some divine status, but the divine familiars of Nanami and also the shrine spirits are there too, so that banquet is not deity-exclusive.