I was wondering what everyone's thoughts were on whether to use h**p://domain.com or h**p://www.domain.com. When I first started got into this over a year ago I made the mistake of building links to both versions of the domain name. This ended being a real b*tch because sometimes my site would jump around in the SERPS, sometimes with a www and sometimes without. I finally ended up switching to www in Webmaster Tools but sincce then I've always wondered about whether to use www or not too. So what do you think?