Did anyone notice during the duel which harry and sirius were fighting side by side, that sirius said "good one james" instead of harry?

that was supposed to happen.
in the books Molly Weasley is always saying that she thinks Sirius sometimes thinks Harry is James..like he's soo much like his father, he remembers all the good times with James and thinks he's with him.
so they applied that to the movie.
they kinda threw it in there, and if you've read the books you would understand that.

Didn't it also turn up earlier in the movie, in the scene from Snape's memory? It's not in that scene in the book, but I thought it was a nice touch to put it in there, suggesting that it was something Sirius said a lot. In the DoM scene in the movie, I can't make up my mind whether Sirius actually thought for a moment that it was James (as Molly thought he was doing earlier), or it was his way of saying Harry was like his Dad.

Well, either way Harry took it as a compliment because he was smiling haha.

Yes I did and I think that Harry noticed too.

I don't remember that..But it sounds familiar. I really don't remember

Maybe this is a reference to how Sirius and James treated Snape? I'm sure they said "nice one" at some point for bullying Snape.
The obvious thing is that Sirius views Harry almost like a brother, like James, and in the heat of the battle he feels he has his best friend back, as Sirius and James both loved combat.

I remember this, because I just recently saw the movie But I think it's kind of sad that the last thing Harry ever hears from Sirius is "good one James" .

I think it's sad that just before Sirius is killed Harry hears him say he's just like his father when he exclaims "Nice one, James!"

I personally really liked that line being in there. It fully shows how Sirius sometimes tends to think of Harry as James instead of just Harry, and it makes that scene even sadder when Sirius dies because the last thing he says to Harry is "Nice one, James!" not "Nice one, Harry!" I thought it was a nice addition on the filmmakers part.

that was suposed to happen, the books show how much Harry looks like his father and the longing of Sirius for James to be alive so he tends to see James in Harry so much that Sirius begins to treat Harry as if he was James

OH, yeah, I noticed that one. Isn't that in the book, though, too? I don't quite remember, and correct me if I'm wrong, but I believe it's also in the book...

Oribiablue, I just read that part in the book and it isn't in there.

Yes it was supposed to happen. It was because he's so much like James.

Yes, and it's surppose to happen.

It's showing that Sirius often think Harry as his best friend, James, instead of his god-son Harry. If I remembered right, after he said that, Harry kind of starred at him for a moment there, didn't he?

I'm pretty sure that was on purpose. It showed how close those two were back in the day, and how much, again, harry looks like his father.