There's not really a difference here, art is art, your tools and media don't really matter, what's important is how its meant to be seen and what it's meant to be used for.
But, people do like to discuss this though and so do we and so we did!
This is our short, condensed vid of the whole thing but we also had a much longer discussion about it for our podcast here: http://www.theduckwebcomics.com/quackcast/episode-250-tradigital-art-digital-vs-traditional