Root vs. Index.html

[DavetheExterminator]

Should I redirect index.html to "/" or vice versa?  Which is better for duplicate content issues?

[RyanKent]

The index.html file name offers no value for SEO nor users. I recommend not using it and directing users to a "clean" URL (eg seomoz.org/ instead of seomoz.org/index.html).

As long as you properly set this up and consistently link to the same URL there are not any duplicate content issues. If you wish to go one step further you can add the canonical tag to your page.