DConf 2013 Closing Keynote: Quo Vadis by Andrei Alexandrescu

[CJS]

In the talk Andrei seems to mentions that D's associative arrays 
are lacking in performance somehow. I'm very new to D, but it's 
not obvious to me what the shortcoming is. I assume it's that for 
some reason it's hard to specialize associative arrays to specfic 
types to give increased performance in specfic cases, but I'm 
unclear why that would be difficult. Could someone please 
elaborate?