The message headers are the only other area in which this information can be found. Reviewing Bruce's document will definitely be the best course of action as it gives great recommendations on recommended values for the URIBL weights. We typically see weights ranging from 5-10, with maximum weights of 20-30 across customer deployments.
Regarding the user submitting items for the spam filter, this will only effect the bayesian filtering check. Depending on how many users are reporting Spams, the list may just not be updated quick enough. If you edit the Bayesian filtering spam check, there should be a value for Messages required for filter update, you can reduce the number from 3000 to 300 so that less mail is required for the learning algorithm to kick in.
Technical Support Supervisor