I own a portal and I want to send traffic from this portal to several customers which all pay for a listing on my website. I want to rotate all positions on my index.php at every refresh of the site. I need this to send equivalent traffic to all customers. So I need to create a rotating system for my website and the question is: will google like it or will they ban my website? Does anyone made experiences with rotating content?
My limited experience has indicated that there is a very good chance that google finds 'random' content on pages, and ignores it (or at least: doesn't list it in SERPS). I guess you could reason that if it doesn't have a fairly permanent place on the page, or at least isn't there on another check shortly afterwards, it's not worth putting in the search results either (since this is likely to be different). I'd guess that this wouldn't be likely to have any significantly bad effects.
Make a fair amount of content stable and just rotate the rest, let stable the description, the title any why not even the keywords (... you never know ...). Google will index your page and if you have enough links pointing at it, it will even index it regularly. My index page is indexed every second day and it randomly changes somewhat like 30% of it's text on every pageview (not for SEO purposes but presenting different customers).
On my advice this should be ok, your rotating content gets indexed as advertisings on pages do. This means it could last longer than normal for your page to get in the index, but it defintively should get into it.
... i know, a lot of coulds and shoulds, but there have happened so many different behaviours on G that it turns hard to tell exactly ...