I have just gotten a fantastic link on a nice PR8 site and it's on the homepage. I've spent about a year building a relationship to get this link.
The only problem is it goes to the www.abc version of our site and our site is on the [abc...] version of the site.
I am a little worried about mailing him to ask to change as he has been good to us by adding the link as it is.
Does this make a big difference to the juice the link passes of is it nothing to worry about as the Search Engines know what is happening?
The reason i'm a little worried as on: Open Site Explorer the www and http are completely different results. I do have the www forwarding to the http - but i was wondering if we will lose any juice because of this or be negatively affected in any way at all.
Hopefully you're not "fowarding" the www to the non-www version of the URL (BTW... BOTH should likely be http except for any pages that need a secure connection like checkouts or forms requesting sensitive information).
If your canonical or prefered version of the home page URL is http://example.com/ then you should be 301 redirecting all requests for http://www.example.com/* to http://example.com/*.
If you request http://www.example.com/ and that request returns anything other than a 301 Moved Permanently HTTP Status then your http://example.com/ URL is likely not getting credit for the link (unless you have a canonical link element in the <head> of http://www.example.com/ pointing to http://example.com/).
But some forums don't auto-link URLs unless they begin in www-- or unless you explicitly include http:// --so you get in the habit of typing one or the other. And then, ahem, you forget to disable the habit when you land in a forum where you don't want the URL to turn into an active link :)