So he's been with us for half a season: first time he has played as top man at an elite club, playing under a new manager coaches and tactics, in front of huge crowds and with new colleagues.
All things considered, I think he's had a very good start to his Manchester United career and compares very favourably to 1st half season for other high profile striker signings like Cole, Saha, Tevez or Berbatov, especially in terms of goals and assists. It could have been better which would have led to an outstanding start, but it could also have been alot worse.
He is still improving certain technical skills of his game, and I imagine Mourinho will recruit future players and tactics around his game so I expect a significant improvement to his contributions, tangible as well as towards other player's effectiveness.
I expect that this time next year we will be talking a consistent world class striker.