Just to add more confusion, I play this song in Eb, because it's my favorite key.

What's really important, of course, is not the key, but the relationship between the different chords in the progression. From this point of view, I would like to comment that I don't really like to play the second chord of the song as a "13th", because I think that this chord has a "strong" character and to me is more suited as a final chord before resolving to the dominant (but not in the case of "Girl from Ipanema", anyway...); as a passing chord between Fmaj7 and Fm7, I would play a "9th" instead.

Another interesting observation refers to the Gm7-C7-Fmaj7 progression: the C7 can be altered as a C7b9 or can be substituted with a Gb7 (I am not sure, but I think that this would be called a tritone substitution; maybe Scott can confirm this).

I just had an idea: what if we all post our personal rendition of this song? After all, like Confucius used to say, an example is worth a BILLION words!