I decided to cover this because I may want to transcribe the melody, and I heard it performed for the 2nd time in my life at Kelsie Gray's trumpet recital tonight. And it's hot.
This piece is fairly modern, so perhaps trying to apply an old form to it is futile. After scribbling some notes about the outline of the piece, I'd say it's in 5-part composite rondo form, looking like this: A trans B A trans C A
The A section is in a rounded binary form which gives the piece the composite nature. The 'a' theme is a fast, staccato section. The 'b' theme is played over a 6/8 waltz feel. I say "played over" instead of "is in" because the trumpet still plays in a duple, hemiola feel, giving this section a cool sound. The 'a' section returns in the piano, which has a solo interlude every time the A section is played.
After the first A section, there is a transition made up of the 'b' material which leads into the major B section, which is a soft, ballad-sounding feel with lots of 7th and 9th chords, giving it a real modern-jazzy feel.
'A' returns, in the same manner it was played the first time.
There's another transition into the 'C' section, which is very similar to 'B' in its modern jazzy feel. This section has a lot of nice tension and release between dissonant, extended-harmony chords that resolve to simple triads - I especially like his use of Db, which is to me the most mellow-sounding triad.
'A' returns again, barely changed from the begninng.