I have a little network of websites that are linked between them. These links are in rotation on all pages of all the sites. My question is, how does Google consider these links?...I mean, sometimes Google will find a link on an specific page and the next time it could be another one on its place...does Google read the list of all the links that are in rotation or just reads the one that is displayed on a given moment? In terms of link popularity and PR, how it works?..are there negative effects?..would it be better to attach the no-follow tag to each link?
If your all website(domain) are on same server then may be google consider it as a spaming activity.so be carefull.....
In terms of what Google will see, you could do it either way, i.e. all the links or just the displayed one. It's thought that the age of a link is a factor in the algorithm, so if they are not all seen, it will not allow your links to age, so therefore probably never reach their full potential.
steve_gts is right, the older the link (indexed by Google) - the more it helps to linked site. If you keep on changing the links, you might not have them at all. Better keep few sites that will link to one site that is important for you, instead of linking all of them together.
i would definatley be careful with this dont think i'd risk it myself, much easier just to get more backlinks from other areas than to lose all rankings on your sites