I was on AA 22 yesterday, LAX-JFK. Speedtest.net defaulted to Dallas as the server. The test was rather disappointing, IIRC only about 0.2 Mbps download (and upload was slightly less).

Later on in the flight it seemed to be working better, though I never re-ran the test. The connection did cut out completely for a few minutes at one point near the end of the flight as well. Glad I didn't actually pay for the service...

And on my outbound JFK-LAX, I saw a guy doing a videoconference with what I assume was his wife/girlfriend, who appeared to be on Virgin America in FC. He was on a mac, but the video was full screen so I couldn't tell what program he was using.