It depends on where the employees currently live. You appear to be assuming that most will be coming from the Princeton area or along Rt 1. I would venture to say many probably live along the I287 corridor in places like Basking Ridge or Hillsborough or possibly down around Freehold. From those places, the commute to New Brunswick would be much easier than getting to Philly. But then, that is just speculation because I don't know anyone who works for Blackrock.
On another note, I was at the Phillies game tonight and they had a "welcome" to Employees of Blackrock on the scoreboard, and not just when they listed the groups attending the game. Maybe they were courting the execs
or it could have just been their Wilmington crew.