It depends entirely on how much is "a bit".
When a gun does develop endshake, it only gets worse.
The danger is, essentially the cylinder is now "slamming" back and forth in the frame.
This can, and will impact damage the frame, cylinder assembly, and even the back of the barrel.
If you continue shooting it until the groups go bad, the gun will likely have suffered permanent damage by that time.
I'd watch it closely, and as soon as possible I'd install some endshake washers from Brownell's.
If you get Jerry Kunhausen's book on Gunsmithing the S&W Revolvers, you will be able to determine how bad it is, and how to install a washer to correct the problem.