This is Hoya cv 'Optimistic', a hoya that I received mislabelled as H. guppyi.  Either way, both are eriostemmas, a type of hoya that grows like the dickens, but rarely flowers in "captivity".  This hoya has bloomed for the past three years; reading up on it I discovered that it blooms only in direct sunlight at the tops of trees in the rain forest. So, I tried putting it in a window that receives maximum sun, and it worked!  Anyway, here is its picture.

And last summer I got the "real" H. guppyi, but it'll be a few years before it flowers ... if I can get it to flower that is!