Panthers General Manager Randy Sexton had a few words in the intermission: “I thought it was a late hit and dirty hit,” Sexton said. “These types of hits have no place in the game. I didn't see the hit live. I was making a note on my game report, but I knew when they didn't show the replay it wasn't pretty.” Holmgren was fast to respond

“Randy Sexton should watch more hockey games,”“It was a good hit. Mike Richards is just doing his job there. If you slow it down frame by frame, I don’t see how you can [suspend] him.

“He went to finish his check on a player who had just passed the puck, and he hit him. His feet never left the ice, and it was a shoulder hit. The young David Booth turned his head, it looked like he saw him at the last second, but as he turned his head, his head took the blow. It would have been a shoulder-on-shoulder if not. It’s a physical game, and sometimes those things happen,”

UPDATE: NHL has cleared him, no suspension will be handed out.

Now the big question is will he be suspended or should i say how many games will he be suspended for?
He was given a 5-minute major and a game misconduct, which is automatically reviewed by the NHL for suspension.
In my opinion it was a clean hit no elbow he didn't leave his feet but the problem was that Booth could not see him coming.

“I just seen him with the puck,” Richards explained. “I was just trying to eliminate him from the puck. He dished it off. It happened so quickly, it’s hard to explain.
“I don’t know [whether it’s legal]. I was just trying to separate him from the puck and he moved or turned.
I don’t have a history of head shots or anything like that. It happened too quickly.”