I got an esplora recently, and after much hassle with drivers, managed to upload some sketches with a windows 7 laptop.
Today, I pulled it out, and tried to upload a sketch with a laptop running 64-bit fedora 17
I got this in my verbose output:
avrdude: Send: S [53]
avrdude: ser_recv(): programmer is not responding
avrdude: butterfly_recv(): programmer is not responding
I also tried again with the windows laptop. Sometimes I got the same error, sometimes arduino couldn't find the Esplora.