I think "playfulness" would be a good term for Collins' poem.
Yes there is a message...No he is not making fun of love poems. He is using metaphors to tell his love what he thinks of her and to let her know what kind of person he is.
Here is a quote from a review
" the marvelous ''Litany'' strikes me as the likeliest new candidate to inspire the question ''Do you know the Billy Collins poem about . . . ?'' What sets ''Litany'' apart is that the words themselves, not just the situation, are so memorable. That's because it capitalizes on some of the oldest verbal conventions in poetry -- parallelism, refrain, the lover's mystical hyperbole -- and simultaneously pokes fun at them. Quoting a snippet of a poem by the Belgian poet Jacques Crickillon (''You are the bread and the knife, / The crystal goblet and the wine''), Collins offers his lover a stanza of similarly lofty praises before asserting himself:
However, you are not the wind in the orchard,
the plums on the counter,
or the house of cards.
And you are certainly not the pine-scented air.
There is no way you are the pine-scented air.
And the poet isn't finished: ''It might interest you to know . . . that I am the sound of rain on the roof.'' It turns out he's a lot of other things she may not have appreciated: ''I am also the moon in the trees / and the blind woman's teacup.'' He's not so hardhearted, though, that he won't throw her a bone at the end: ''But don't worry, I am not the bread and the knife. / You are still the bread and the knife.''
By MARY JO SALTER
Published: October 20, 2002