martinibuster - 1:38 pm on May 22, 2013 (gmt 0)
Hey Jake! Didn't we have a late dinner together at Pubcon NoLa?
...it could create some duplicate content issues.
That is no longer an issue. Google and Bing are able to detect URL Parameters that lead to the same content and consolidating the link equity to the best URL. Duplicate content issues is not really something to worry about for this topic we're discussing.
From Google - Re URL Parameters [support.google.com]
When Google detects duplicate content, such as variations caused by URL parameters, we group the duplicate URLs into one cluster and select what we think is the "best" URL to represent the cluster in search results. We then consolidate properties of the URLs in the cluster, such as link popularity, to the representative URL. Consolidating properties from duplicates into one representative URL often provides users with more accurate search results.
Nevertheless, IF the OP is going ahead with the tracking URL then Jakes suggestion of using the rel=canonical is a good idea for the sake of helping the search engines. But keep in mind that rel=canonical is not a directive, it is a suggestion. A directive is code that search engines/crawlers must obey. A suggestion is not. The search engines will take the rel=canonical into consideration, but will not actually obey it. More information about that here [support.google.com].
Odds are, the tracking variable is going to make it look like they are a commissioned site.
That's not really an issue either. Google is aware of all the major affiliate networks and detects them and discounts them. Tracking variables are unique so they won't be handled in the manner that affiliate links are handled. More information here [webpronews.com].
Nevertheless, it's still a good practice to idiot proof the way we do things. Search engines still make errors from time to time.