If he is on vacation, great for him ... and that is one heck of a vacation, but definitely not unheard of at all.  I would seriously worry if it got to be a month+ and nothing.  Could have been so many things.  I'm sure he will appreciate everyone's concern when he does return.  He is thought of fondly by, dare I say, pretty much everyone. 

Here's to his happy return.

-Tim

PS> What were the last threads he was involved in about?   I assume nothing mentioned was out of the ordinary?