Ninjas, son.
So, we reach Naruto, the show currently keeping the US anime industry's profile high (along with the more recent Bleach). Naruto, the manga, began in 1999 in Shonen Jump and has become on of the biggest multimedia properties for that magazine. The anime started in 2002, and it's popularity in Anglophone countries was propelled by the advent of bittorrent. Indeed there's probably an argument that they propelled each other to some degree.
The show is set in an anachronism filled fantasy world, where numerous ninja clans compete for work from different governments. It follows the adventures of young, 13 year old trainee ninja ORPHAN called Naruto. Who just so happens to have had a powerful demonic spirit bound into him.
The series, like Bleach is very much a template for how Shonen Jump strips tend to proceed in their lifecycle. They normally start with a short introductory story, then a longer self contained story, and then once the series is established and a hit you get the “big” story the author wants to tell.
Now, Naruto starts well, but hits a problem once it hits that big story. Much like Bleach's Soul Society arc, creator Masahi Kishimoto introduces far too many at once and also goes for the easy tournament plot route that has proved popular in Jump strips since Akira Toriyama almost accidentally hit on the formula in Dragonball. And then it just begins to meander with no end to the current storylines in sight.
In fact it meandered so much, it's audience effectively outgrew the main character. Reading about a 13 year old ninja may seem the epitome of cool when you are 13, but by 2005 that 13 yr old kid who started reading Naruto in 1999 is going to be 18-19. So much like the leap from Dragonball to Dragonball Z, Kishimoto leapt the plot forward 2 and a half years and began Naruto: Shippūden.
As a disposable piece of pop entertainment, the show stands up quite well. The episodes vary in production quality greatly, but it has produced some truly stand out pieces of work from Norio Matsumoto. It's only when you compare it to other Jump titles, past and present does the series begin to look a little weaker.
But the lucky thing is that the bulk of the audience for the show won't be that familiar with them leaving it only having to really be rated against Bleach and One Piece. One of which it is more successful than, the other it comes short of matching.
Personally it's my least favourite of the three due to the meandering nature of the plot, the relative merits of the other two and the fact that Naruto has so few influences that you can see them clearly.