My philosophical prejudices lead me to believe that the necessity of dark matter/energy implies a shortcoming in our understanding of gravity.
Clearly, there are shortcomings at the quantum scale, but this is another matter entirely.
I ran across an article on physicsweb where a scientist proposes a test for a MOND theory.
http://physicsweb.org/articles/news/11/3/12/1
Point of the thread:
1) Does anyone share this philosophical prejudice?
2) What are your educated opinions on MOND theories?