The mark making of the pencil in this portrait is so brilliant that you have captured and conveyed a great likeness of the actor, especially through the features like the eyes, mouth and nose. The charm and slight playfulness of the actor is also shown, from the glint in the realistic and well drawn eyes to the very warm and open smile, which has been achieved through great depth of tones.
As far as any portrait goes, this is superb and the talent you show is astounding, and as far as i can tell the face has been focused on the most. This does work, to show his emotion and warmth, but perhaps more details and tones on the hair and neck/clothes would also bring more realism to it, as the hair does seem to fade in the background.
However, overall it's a brilliant piece of work that looks very realistic and photo like. An inspiration to me and i am sure, many other deviants. Astounding and excellent.

I love your sketchiness: how you can bring out the likeness of someone with just casual gestures is wonderful, let alone the personality. Also I like that the most detail is on his eyes and smile, which draws your eye. The farther you get from the 'important' stuff, the more the detail fades out. I think the sharpness of the lines of his jaw (his right) are perhaps too dark; they draw my eye a little more than they should, but his eyes and smile are so nicely done that I get pulled back away from it. I hope to see more work from you: as tired as you've been, it doesn't seem to have hurt your drawing skill.