I have a large network of unique, related websites. What is the best way to interlink them ? I assume linking them all together is a bad thing...
Linking them all together is not a bad thing. It is a very good thing. One way links are better than reciprocal but pick and choose what ones you actually want to link off of. I do web design so by linking all the sites I develop to my web company gives me a better rank.
As a general rule, you should link from the less important sites to the more important sites. Also, avoid reciprocal links.
How many sites are you working with? If you're working with over 100 sites, I'd keep recips to a moderate level and link like billybw said: from less important to the main site.
Like 50 sites... Hmm now im getting conflicting info, so my pr4 sites should link to pr5 and pr 3 to pr4 or go straight to pr5?
You are supposed to bleed the PR down to the weakest site. Link the highest to the next highest and do that all the way down with one way non reciprocal links. I would not recommend reciprocal linking if all the sites are sitting on the same network.
What if you have one strong site and want to build say 40 micro-sites with keyword rich domains related to your industry to try and get those sites ranked under those searches. What is the best approach then? I see two options: Option 1: Have these mini-sites link to the main site to drive traffic and create backlinks. But I assume linking from the new micro-sites to the main site won't do much good for the main site. Option 2: Linking from the main site to the micro-sites could help boost the new sites and get them ranked - perhaps the mini-sites could have the means to list build so you don't need to send traffic to the main site. The only problem I see with option 2 is how do you link to 40 sites off the main site and not look bad? Thoughts?
Why does everybody overlook the effect of a good internal link-structure? I can give you examples of websites with a PR5 for the homepage and an unranked links page, simply because the link-structure has not been taken into consideration and linkjuice diffuses rapidly to random pages. The websites in question are into some untargeted link-exchange programme with a few dozen of other related and non-related websites, each having the links from this link-exchange group on their links page. Drawdead, linking all your websites together through reciprocal links or one-way links is not necessarily a bad idea, but it's no guarantee to success. If you want, I can help you with setting up a proper link-structure. PM me if you're interested. I won't do that for free, though.