Ok, I just had my car in the shop last week for the following:
Replaced LIM gasket, supercharger gasket and o-rings
Cleaned throttle body and replaced gasket
Coolant flush, replaced with Prestone All Makes All Models
Oil change
Tire rotation
It seems to be running the same as it was before I had the work done except that now I've noticed my steering wheel shaking when I get up to about 55-60 MPH. It'* pretty strong, too! Any ideas as to what is causing this? Thanks!

Sounds like an out of balance tire. Try swapping the fronts to the back and see if it goes away. You probably need to get them rebalanced

Ok, thanks for the reply. I just got Pirelli P-Zero Neros put on in the spring - I think about 6K miles ago, and this is the first time I've had them rotated.