It's funny that I found this thread tonight. My dad just got done telling me that when he was little, he saw a huge 6 engine bomber fly over his house around the year 1955. He told his mom and dad, and they didn't think anything of the sort existed at the time. After a bit of research, we found out it was a B-36 Peacemaker, which is a pretty damned cool push prop bomber...

Sorry for the hijack, just thought it was interesting.
As for the picture, I don't see engines on the wings, I'd go with a small private jet as well, particularly because of how close the trails are together.