Good framing and well captured - was obviously a fairly rapidly moving subject. On sanning and JPEGing there may be some hints in my article on scanning on this site. The very nature of JPEGing means you'll lose data which does affect picture and colour quality - to check the result of a JPG (having saved the original image as a P/S file or whatever image software you're using), open the JPG file in your browser (i.e., Netscape or IE - File -Open and select the image). If, for example, you've lost some colour saturation, increase it a little in the original and make another JPG and check again. Also, check your image app. colour settings are set to sRGB (this will minimise the colour shift).
Wonderful capture Brendon. I can't help you on your jpeg format question as I have some shots like this myself of some parachuters and altho in the view finder they were brillant and beautiful after scanning and saving they weren't nearly as vibrant as I thought. Anyway this is a cool grab shot.