Well, dealing with the creative responses of my co-workers after the first video was so much fun -- comments like "The man may excel at computational data storage and analysis, but he needs to learn a thing or two about whiteboard real estate" So, why stop? The answer is: we already taped the second one and the marketing team really doesn't understand the concept of sunk costs.
In the new video we spend some time talking about benefits of the replication based storage model over backups for protecting your data.
Basically the issue comes down to a couple key benefits of any replication based strategy:
1) Since you are replicating continuously, you don't have a discontinuous process that is intrusive to regular operation that needs to run regularly and more importantly with replication you only need to back up each piece of content ONCE. With a backup model you have to backup each piece every time you do a full backup. This means that the cost and complexity of backup becomes unsupportable once mailboxes get very large. Replication really only copies the mail once so it is continuous and the cost and complexity are proportional to delivery rates NOT how long each mail is kept.
2) Because the copies are fully up-to-date all the time and are true, validated replicas, the time it takes to restore (i.e. get the backup up and running) is much faster in a replication model.
There are more benefits of replication that aren't covered. Things like being much more secure against logical corruption in the storage stack because the write paths are so different on the primary and replicas and the ability to spread the replicas around a continent and get a true disaster recovery benefit. But we can go into more detail on those issues another time.
At this point, I suppose some might be wondering if classic backups are good for anything. Well some people might very well think that. I couldn't possibly comment. At least right now... But I'd like to hear what you think!