A quick check on fares for this coming Friday afternoon (5:00-ish) PHL-BOS gives the following results:
Regional Coach: $124
Regional Biz: $160
Acela Biz: $200
Acela First: $287
Getting back to the OP's question about upgrading from regional coach (which is what he said his employer will pay for) to Acela. It's a pretty big jump from $124 to $200 just for a seat with no drinks or meal. And it's a huge jump from $124 to $287 for a seat with free booze and only "decent" meals. I've done regional once (recently) and found Acela Biz to be more comfortable.
I don't see any comments in this thread about Regional Biz, but at most, I would go Acela Biz and buy something at 30th street station in Philly to eat on the train...and still have money left to buy beer on board.