database discrepancy

I posted a while ago regarding admin permissions, when adding new admins I couldnt choose their permissions in the ACP. Long story short, I've been busy with other things and have recently revisited it. Inside the "Live" spoiler you can see what is shown on our live version, and similarly...

So I thought I was having a database crisis, long story short it doesn't appear I am. I compared table sizes for my current installation and a two week old backup. A few tables seemed to drop in size which caught my eye and I'm not sure if I should be concerned or not. Left columns contain...