It will be another year or two until the IR scores kick in. GMAC is collecting data right now.... they are about data. That's their mission in life
They will try to establish a correlation between IR, Grad School GPA, Employability, and whatever else they can. Right now the strongest correlation they have is the relationship between undergrad and grad GPA's (even more so than the GMAT), which is understandable.
P.S. Grad school GPA is a measure of Success in BSchool. (it is not getting a job, or salary level but rather grades that determine if you were a success.
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