I've owned both. As far as the Standards are concerned, the MIA is simply a guitar I would choose over the MIM. That has to do with,
The feel of the neck shape and nut width.
The 2 point tremolo system,
22 frets,
and over all nicer finish.
(one could argue about a more resonate body due to choicer cuts of wood, but I wont).
And on that last point, the finish on a MIM guitar can be excellent, I'd still rather play the MIA. I only use a strat for recording at home, so I do use a MIM standard with Fender 57/62 pickups. It's a fun guitar and it is nice.
But still the stock 2008 MIA is nicer.