This almost seems like an oversight, as all the other fields are sortable, except for user name.

I noticed this wasn't included in 3.6, even though I think it's an easy addition. Any possibility that this can be included in the next release?
 
Doesn't this bother anyone else?

I agree it would be useful - although we usually only need it when looking for all orders for a specific customer — so the search function generally works for us
 
Chris