you never know which one is bigger. because its nasa, you cannot support your claim in public i think :) and i don't see NASA in the list of 10 world's largest databases (http://pandidba.blogspot.com/2014/01/top-10-largest-databases-in-world.html) but the company i work for is there. Again that's a system spanning multiple data centers across the globe. mind you, we are talking about wordpress. if your system is of such scale, you are not doing to install wordpress and be happy with that.
and when mentioned "index fragmentation", you are just proving my 3rd point (in my first reply). that's DBA responsibility
i "happily disregard"ed because its not an issue. people who reported issues, we fixed them. But we don't like to spend too much time discussing no-issue.
So unless you have found some "real" issues in our software, we will not be replying to this thread.
Thanks.