Black spots on some of the leaves, especially the older ones, are perfectly acceptable, most Oncidiinae get these when exposed to the correct amount of sunlight-- in fact, some will not bloom without it. It looks like a very healthy plant with some good new growth.
And I'm nearly completely sure you have purchased a Miltassia C.M. Fitch 'Izumi' -- take a look here to be sure, if you'd like.