jakebohall - 5:27 pm on May 23, 2013 (gmt 0)
This will always vary by site and conversion type. In most cases we try to identify all of the varying types of conversions (downloads, sign-ups, previews, likes, etc.) and assign them a value.
We mostly use Google Analytics, so once you have the goals set-up, you can view them across any channel, keyword, referrer, etc..