Depends on the air INLET temp as well - if you're moving, then the underhood area (stock air inlet in particular) is getting some airflow and so probably is not at 180 degrees. If that's the case, then you may or may not have 180+ between the turbo and the IC. The more important pipe to insulate is the cooled air from the IC to the TB.
I know on "good" IC's the IC will bring the charge to within x degrees of ambient - almost no matter what the inlet air temp is (note: ALMOST). In that case a CAI may or may not be necessary as the CAI is BEFORE the IC.
Our IC capacity isn't near high enough, so the air temps pre-turbo are important - it helps make up for lower IC capacity. (Water spray on the IC would have a similar effect, methinks, but may accelerate the corrosion of the IC.)
Only point is that the more important pipe to insulate is the IC-to-throttlebody pipe. Insulating that pipe, as IRR suggests, doesn't trap heat but rather traps the "absence of heat" in that pipe (the intercooler having removed some heat from the charge air).