I have a website that has a permanent redirect from a non-www site, to a www-site. (same domain) The question is, how does this affect link building, especially at Google, if I have some links pointing to the non-WWW site, and some to the WWW? Some backlink tools that I have used show the links pointing, not to the domain, but to the site exactly as entered. Do search engines (most or all) resolve this issue? For Google, specifically, can anyone comment on their particular knowledge or experience regarding this issue? Obviously, consistency is the best policy. However, I had some links created by someone else for my site, and they used the WWW version. I have since put the redirect in place, knowing that it should have been there, anyway... Thank you.
The SE's see each version as different (www vs non www). In the future, try and have all your links point to one version if you can. It's obvious you can not control how people link to you on their own, but you can control submissions and link exchanges etc.. The 301 redirect you implemented should go a long way to consolidate your link popularity over time though. this tells the SE's that the url in question has permanantly moved, and to therfore transfer the redirected versions link popularity to the new domain. What i mean by this is that any link building done to the non www version should eventually transfer over to the www version. Most of it at least
Yahoo is the worse at handling 301's Google normally corrects itself after a backlink update or two, Normally on the second backlink update I have noticed (although in very limited tests, like about 6 or so). As you rightly say, get them changed to the proper domain is always the best option