Ahhhh...breaking in a cartridge.

While I'm pretty sure most loudspeakers and components do have some break in period, I KNOW cartridges do break in because I've heard the diminishment of surface noise (and other stuff, which may be more subjective) over time. 

I'm breaking in a new Audio Technica ART9 cartridge.  I'm 5 hours in and my ear is either getting used to it or it's sounding better. :)  This is not much time, I know.  I am trying to listen to the same records (about 5 albums) over and over, of which I'm well familiar to see how things go.  If I had to sum up the break in thusfar in one statement I'd say things don't sound as tight and reserved. 

By the way, this cartridge is going to be killer.  It's tonal balance is superb.  Not one region of the spectrum is emphasized.