IMHO Bargnani cannot be compared to any other european guy playing in the NBA right now.
Nowitzki? At the same age, he was playing in the second german league (wurzburg) and he didn't show anything of what we're looking today.
Skita? He was playing in the same european team: sorry, playing is not the right word.....he was warming the bench, carrying the water and spinning towels. (remember m.l. carr??)
Gasol? Different player; Pau has a better post game but is a worse shooter.
Darko? Darko who?? Even in Europe he was like an UFO.
Don't know if he's really a n°1 pick, but sure he will be a good NBA player: the team picking him will be happy to see a guy with a good working attitude and an easy learner. Some pounds around his bones will make him a tremendous power forward, hoping he won't lose his feet quickness.