it was offsides but really petty. Tough to overturn.
Whether or not it was offside (it wasn't*) is really beside the point considering the spirit of the replay rule:
"I think it’s worked well," said Mike Murphy, NHL vice-president of hockey operations. "The reason we instituted it was so that we could get the egregious calls particularly right, ones that everybody alive sees and says, ‘This is the wrong call, it’s a screw-up.’"
This was not an "egregious" missed call but even if it were, the standard for overturning a call on the ice is conclusive video evidence which no one has. Secondly, many people are focusing on the lifted skate (which again, there is not a still or video replay anywhere that shows it was lifted) when in fact possession of the puck negates the necessity of keeping both skates on the ice. Forsberg had possession of the puck at the blueline, thus no offside.
Taking the 1st goal in game one away from the visiting team is a tough blow but every team has to overcome some adversity - last team to complain should be anyone playing the Pens who have more lost games to injury than any playoff team.