I'd say at least 1/2, maybe significantly more, DCI. I remember something vaguely along those lines from last time. I read one article that implied that all 125 slots we are trying to get from USAir are currently "Express" slots.

Here is one old article:

Delta, US Airways announce massive DCA/LGA slot swap deal | ATW Online

One of the highlights:

"DL said it will more than double the number of destinations it serves from LGA, including 12 cities not currently served by US. It said it will operate "larger jets" from the slots it is taking over from US instead of the turboprops US/Piedmont operate currently."

But "larger jets" than a Dash-8 could absolutely mean 70-76 seat RJ's.

Not only that but there was major buzz at the time at CPZ/CMR about huge LGA growth should it be aprooved. Those two things lead me to believe that the "growth" will be mostly outsourced planes rather than Delta pilot jobs, although we may end up with some.