Naruto Shippuden is based on part 2 of the manga series. Shippuden is a continuation of the Naruto saga and the storyline starts 2 1/2 years after series 9. Naruto has returned to the village after having left to train with Jiraiya. On his return he realizes that unlike his friends who have progressed to higher ranks. He is still a genin and Naruto finds this a little hard to take.
Shippuden has been segmented into 2 major arcs; in the first team Kakashi and team Guy have to save the sand village's Hokage (Gaara). We get to see how everyone has progressed and their new powers. After the two teams return to the leaf village, team Kakashi get a lead on how to find Orochimaru's hide out (arc 2). But they have to replace Kakashi (as he is still recovering) and Sasuka. So there are 2 new members added to team Kakashi the new captain to stand in for Kakashi while he recovers Yamato and Sai. Sai is really weird and does not know how to act in society and therefore says everything that is on his mind. And when he first meets Naruto he says some colourful things to make Naruto hate him. Sai does the same thing to Sakura and both Naruto and Sakura end up thinking he's an asshole but agree to work with him in order to save Sasuka.
(This is the second opening with the new team members.)
There are some really kick ass fight scenes in both arcs and this series just keeps getting better and better. I watched the first 43 episodes in 2 days and now I am forced to wait until Friday each week to watch the new episodes. I have fallen for this anime in a big way and I would recommend this to anyone. If you watched the original series and did not like it then give Shippuden a try I am sure you will like it. The grate thing about this series is you really don't need to watch the first 9 series to start watching this one (although I would recommend that you do). Also you need to watch past the end credits as there are some funny bits at the very end.
So I have been digging around to try and find out how far they are going to take this series. If you look on Google you will only see 46 episodes but I have found out there is going to be 55 episodes with the last on airing on 04/10/2008. We can only hope that they will continue with more after that. There are also 2 movies that are connected with Shippuden the first came out in 2007 and will be released on DVD in April this year so you can look for that on the net in April. The second movie is due to be released in Japanese cinema in the summer. And in the opening credits of episodes 40-41 you get a little taster of what’s going to be in it(watch the fiest video I posted to see it).
This just proves my long standing point, if you want to watch good anime and not wait for it you need to learn Japanese. And this whole experience has made me dig out my old Japanese books and search the web for classes.