This review (like all others) should be taken with a grain of salt. However this is especially so with Astro Boy as it can be very polarising among 'hardcore' manga readers. This is mainly because it does not conform to many of the conventions which one would use to separate manga from traditional 'western' comics. I admit to being a huge fan of the character, however I understand why others do not share my view with this particular franchise.
Astro Boy is not a single story spanning 23 volumes but many individual 'episodes' written over a 30 year period. Added to this confusion, the (current available ttranslations) volumes are arrange not in chronological or publishing order, but as Tezuka wished, with his personal favourite and most popular stories first with his least favourite appearing further down the line. This does not cause continuity problems as such (although be prepared to see Astro's birth at least 3 or 4 times with slight variations within), however the episodic nature of the stories means they are self contained within themselves leaving little room for character development or dramatic universe-altering plot twists. Because of this, and the large number of individual episodes, it is hard to judge the work as a whole. Some of the best episodes such as 'The Greatest Robot on Earth,' or the epic 'Once Upon a Time Astro Boy Tale' (the longest story running for 3 volumes) are truely great reads. But while the good stories are fantastic, there are some bad and mediorce ones. Nothing truely terrible, but nowhere near the same standard as the best of them. Another factor to remember when judging the stories is the audience and context - young boys in 50s and 60s Japan. Astro Boy struct a nerve in this era post WWII, which for western readers is very hard to grasp. Although we (non-japanese) and even some current generation Japanese may not see this series as the cultural icon those who grew up with him revere, the best stories of the series are still hugely entertaining today, especially for those in the age group they were originally made for (young boys). It is worth doing some research and isolating the best volumes in the series, and perhaps sharing them with a young family member for a 'old fashioned' introduction not just into the world of manga, but comics in general. For the younger crowd, Some of the best Astro Boy stories still tower over many newer manga aimed at children.
When viewing Tezuka's work one instantly notices how 'un-japanese' it appears. This is mainly due to the influence early american cartoons (such as Pop-eye and Disney) had on him during the 40s and 50s. Settings are usually 'futuristic art-deco' in appearance while the character designs have exagerated features common in early western cartoons. I personally like how this style looks, separating it from other generic character designs - however this same diversion from current designs is what may put many off his work. I will say that the action sequences (and Astro is filled with plenty of them) are very well done, especial the way Astro is shown flying and fighting other robots.
The supporting characters are well defined in their role, although they do not undergo any form of development over the course of the series. While the characters are not the best in manga or anime, I get a sense that they further development would just interfere and confuse, adding nothing to the characters at all. It is very much a case of keeping them simple, although well defined in the process. Although this is not the case for every character, Mustachio, Ochanomizu and Uran are especially well presented providing entertaining distractions throughout the series. However the strength of the franchise (and the 10 I have given this section) comes from Astro himself. I find him to be one of the most endearing characters ever created, who you can not help but cheer for. From a rather sad birth and rejection by his original creator, constantly being underestimated by everyone making him an underdog in most situations, he is also one of the first to be blamed or rejected (despite his good deeds) by human society when anti-robot sentiment arises which it seems to do often. Being a robot he is often seen as disposable by others despite all he does for them. This provides an underlying tradgedy to his character, which makes his constant struggle for justice and friendship despite these prejudices all the more endearing. He is also a refreshing throwback to the moral certainity of characters like Superman before him - striving to do what is 'right' without question. It certainly reflects the optimism of the 50s before the world became more cynical of these types of 'heroes.' This may not be to everyones liking (seeing as the more realistic anti-hero continues to be popular across all media), however one cannot deny the charm of this 'old fashion' archtype.
To sum up, Astro Boy is a great series aimed at a young audience. While it is not for everyone (epecially the older readers who expect depth in their stories and characters), if one is in the right frame of mind to enjoy some light, childish action stories with a bit of slapstick humour thrown in, you will find this Astro Boy is definately worth a read. The art style and characters reflect an older time, baring little resemblence to our conceptions of 'modern' or popular manga today, however this should not be a barrier to its enjoyment. In my opinion, it is the strongest representation of Astro Boy the character out of the entire franchise. While I do not see many people (besides hardcore fans such as myself) picking up every volume, if you enjoyed the 1960s or 1980s anime series, it is worth tracking down the corresponding volume to your favourite episodes as they are often far more detailed and just as entertaining. For those wanting to witness the mediums or Japanese popular cultures development, there is no better starting point then Tezuka 'The God of Manga's' most popular work. But most of all, if you know a younger person and want to introduce them to the world of manga, Astro Boy is still a great read to get them interested in comics and graphic fiction.