A reader wrote in with the following question/complaint about Senderbase.org. I'm going to post this one anonymously. The reader wrote, "I would like to request a review of senderbase.org. I would like to know if I am the only one that has communication problems with them. Their delisting instructions are basically non-existent, and my last attempts to communicate with them have takes upwards of two weeks to even get a response. I believe the listings last an incredibly long time and that their communication and delisting process is extremely poor. I would like to know what your opinion of them as a reputable RBL would be. Perhaps it is just me with the problem."
Senderbase.org is an Ironport/Cisco reputation system, and my understanding is that it's used by various Ironport spam filters all around the world. I'm not specifically aware of anybody having any problems with it. I, personally, haven't experienced any issues with listings -- I don't even know that I've ever had a client with significant issues traced back to a reputation issue as measured by them. So, by default, I start from the premise that if Senderbase.org says you have a bad reputation, maybe the issue is that you have a bad reputation.
Since it's not really an RBL (DNSBL)-style service, and I haven't publicly published stats on blacklist accuracies in over two years, I'm not really in a position to "write a review" about them. But, what I will do, is post this note here, and invite other folks to share their experiences here, in comments. If you would prefer not to comment publicly, feel free to contact me here. If there's enough interest, I pull together information from various reader responses and post a followup.