There has been many debates between the issue of intercooling and non-intercooling.  Here are some facts based on Corky Bell's book called Supercharged!.  Here is some interesting information you should considered when you plan to get a forced induction system.

Before we start, here are some legends you should understand:
+ = Plus or Sum
- = Minus
x = Multiply
/ = Divide

Here are some formulas will be useful:

Desired Power = stock power x pressure ratio x density ratio x volumetric efficiencies ratio x drive power efficiency

Volumetric Efficiencies = supercharger volumetric efficiencies / engine volumetric efficiencies

Pressure Ratio = desired power / existing power or
                             desired power / stock power x pressure ratio x density ratio x volumetric efficiencies ratio x drive power efficiency

Density Ratio = original absolute temperature / find absolute temperature
Root:
Non-Intercooled = 460degrees + 90 degrees / 460 degrees + 200 = .83
Intercooled = 460degrees + 90 degrees / 460 degrees + 107 = .97

Centrifugal:
Non-Intercooled = 460degrees + 90 degrees / 460 degrees + 170 = .87
Intercooled = 460degrees + 90 degrees / 460 degrees + 102 = .98

Lets plug in some numbers and make it real.  Now we will be using our first generation 1UZFE.  A car is rated at 220 bhp and our desired bhp will be 300.  Lets use these formulas and see how it will affect the outcome between intercooling and non-intercooling.  The below table show amount of boost require to achieve 300 bhp

What the above table saying is that for a 220 bhp to make 300 bhp.  It would take a 10.1 psi in a non-intercooled root style supercharger system to make 300 bhp in the same intake/chamber temperature as a 4.7 psi intercooled Centrifugal supercharger system.  In another word, it will take a 10.1 psi from a root style supercharger to make the same power as a intercooled 4.7 psi from a Centrifugal Supercharger system.

Here is an database that I have complied using 250 bhp as our stock horsepower and comparing Root supercharger and Centrifugal along with intercooling.  The boost require for a intercooler Centrifugal system to make 400 bhp would be around 6.6 psi vs. non-intercooled Root Style 12.52 psi.  The below data is calculated using Corky Bell's book and formulas.

Full data from Excel Spread Sheet Boost Calculation and Pressure Ratio

Pressure Ratio = desired power / existing power
PR = 400 / 250 = 1.6  The pressure ratio can tell us the boost pressure needed, as pressure ratio of 1.60 mean that the boost pressure is .60 of an atmosphere above atmospheric pressure of 14.7 psi. 
Boost = .60 x 14.7 psi = 8.82 psi that would be intercooled root style supercharger.

Density Ratio = original absolute temperature / find absolute temperature
In order to begin our density ratio, we need to know about each type of supercharger and its thermal efficiency.  Here are the comparison of three popular type of superchargers:
 

Here is what Corky have to say about intercooling: "The intercooler can rescue this bad temperature situation.  Let's look at the whole picture again when we place an intercooler between the supercharger and the engine.  Assume the intercooler will remove 85% of the temperature put in by the supercharger.

To calculate the final intercooled chamber temperatures, we use the same procedure as in the previous section, inserting the intercooled temperature gains from in the temperature formula for a 9:1 compression ratio.  This shows that with intercooling, we can run substantially higher boost before reaching the arbitrary 1075 degrees limit: about 10 psi for roots and 13 psi for centrifugal and twin screw.

Although this exercise in numbers is full of approximation, its easy to show, for example, that you can run 40 psi boost intercooled at the same chamber temperature as 8 psi non-intercooled".

Here is an extreme comparison between low thermal efficient and high thermal efficient supercharger.  Secondly, we also compare a non-intercooled root style supercharger with intercooled centrifugal supercharger.

Non-intercooled root style supercharger Vs. a intercooled centrifugal supercharger

Below are the comparison between intercooled Centrifugal and Root Style Supercharger and along with non-intercooled.

If you compare a non-intercooler root style at 10 psi vs. a intercooler centrifugal at 10 psi is 130 degrees F to 13 degrees F.  Its also 100 degrees difference at 10 psi.  The above data is from Supercharged! book page 40 and 42 ISBN 0-8376-0168-1