Absolutely; native filtering support to exclude the domains of my choosing would be the killer feature for me that would make me switch to basically any search engine. I'll even sign up for an account there, and all the possible privacy/query logging that entails, to maintain the blacklist state. Browser userscript addons are just too clunky, screw up the number of results per page and don't work on image searches.

Let me block tabloids, hate sites and click farms natively and I'm sold.