A while back, I wrote a piece about using long guns for home defense. http://larrycorreia.wordpress.com/2007/09/20/carbine-vs-shotgun-vs-pistol-for-home-defense/
I did this after a request from pax at Cornerd Cat. She recently wrote a piece about the advantages of pistols for home use.
It is a good article, but I’m keeping my rifle as my primary. We may disagree on what we personally use, but we agree that the most important factors are finding the tool that works best for you and learning how to use it.