All scheduled deliveries are E170. Classes are fairly evenly split: newhires to the 170 for growth, and to the 145 to replace upgrades. No 170 FO has near enough seniority to upgrade yet, so all 170 CA's have come from the 145, leaving plenty of vacancy in that fleet as well. Upgrade right now is around 20-22 months, but who knows where that will go. Too many details are up in the air with this whole USAir/MDA thing right now to make any kind of definite statements as to what will happen.
As for the J4J, there are a few guys that have come on from United, the program there is a guaranteed interview thing, not a specific ratio program like the U J4J was. I have no clue if any or what kind of J4J might get attached to the ex-MDA 170's when they come over.
LGA is the original ERJ base for us, has been since the first delivery in 1999. It will stay for now, hard to say long term what the U RJ deployment plans will be, but it's likely to stick around.
If you want to research pay, the scales on airlinepilotpay.com are correct, and the whole contract is available on the public side of the IBT747 site.
..CT