Concept and Storyboard artist, Derek Thompson, is a great example of storyboarding techniques. Working at Pixar, here is an example of Thompson's work on the film Wall-E, capturing the first memorable scene between Wall-E and Eve in storyboarding clarity.
The particular use of colour really helps to emphasis key areas in each shot, while providing a pleasing aesthetic quality to the storyboard as a whole, where additional effects such as blurring helps convey the intended type of action within the particular shot.
Interestingly, in an interview Thompson notes that he has started to produce in digital with his storyboarding techniques, later turning the majority of the storyboard into a frame by frame process to form a story wheel programs such as After Effects and Photoshop. In this way, problems can be identified and ironed out quickly in an economical and focused manner for best results. You can read more of the interview here.
Derek Thompson has also produced a Gnomon Workshop dvd covering conceptual storyboarding with digital mediums. From what I've watched so far, he reveals his interesting process of using layer comps to capture a series of shots with a basic touch of animation. Its most insightful and inspiring, which will no doubt prove invaluable when creating my own storyboards.
More info here
You can find more of Derek Thompson's work on his blog, DerekMonster, here.