I have been shooting with Canon 550D for more than 2 years. Last time I shot a lot of landscape. In my opinion, It is fairy easy to shoot. You just need to peek from the view finder and press the shutter.
Since early 2012, I have tried a few portrait shoots and realized that it is not an easy thing to get a good portrait. You need to teach models how to pose and guide on their poses. Some people just shoot whatever the model pose for them and it turn out not good in photograph likes model looks sleepy, boring and not natural. As model cannot see themselves, photographer has the responsibility to guide them along.
Some people look very nice in reality but not good looking in photos. Some look very normal in reality but they know how to pose and their photos look amazing. In my opinion, it is very important for models to know how to express mood with their eyes.
In addition, photographer need to find different angles and frames. For instance, take photos from the top, below, side etc. If they take photos as what they see, it will be a boring portrait. This is not my tip. I read it from online forum.
Some people really want their photo taken nicely but they don't know how to pose. For me, I saved a lot of impressive photos in my phone and show to them. So that we don't waste our times in thinking for poses.
There is no strict rule in photography and everyone have their own technique of taking photos. I just want to share my personal experience about portrait photography. I need to learn a lot of things like lighting and retouching. Also I need to upgrade my camera body and lens. :)