I have to say that I find it pretty easy to take concert pictures. These examples were all taken with my point and shoot Olympus C-5000. It's a 5.0 megapixel, with 3x optical zoom. I didn't change any settings for these pictures(mainly because I didn't know how to use them until the last couple of weeks spent on this board). I'm not sure what the digital zoom is, I think 10x. I'm sure I couldn't get our digital Rebel and 75-200 lens into the stadium.
My theory is first take a lot, you're bound to get some good shots. And you have to
make sure an object or person is exactly in the center of the picture for it to focus correctly(or hold button down halfway and reposition).
This 1st one gives you an idea how incredibly far away we are seated at this U2 concert in St. Louis, Dec 2005. Top section, nosebleed about 8 rows from the back.
This one taken with optical zoom. I wish I knew how to make these bigger so you could see how clear they are.
Here it is cropped a bit.
This one was with digital zoom and it is a bit grainy
And I can get as close as this with digital zoom, grainy but I thought pretty good quality for as far away as we were.
I just keep wishing one of these days I can afford closer seats, so I can really get some good pictures.