Finally got round to picking up the half done translation. Pretty hard to believe it's been two years since then. Time flies, eh?
If I wasn't a software developer myself it would have been quite tricky translating all the parts about programming. Other than the finished translation, you'll also find I've added Shinkai's Twitter feed to the bottom of the site and also a new guestbook feature! Anyone still remember those? You know, those days of dial-up 56k modems and before social media sites took over, it was a page where you left a little message for the website owner and its visitors.
Anyway, as with the previous stories, it contains a lot of new material - a lot more which should help clear up any questions you may have about the final episode of the movie. You can view a detailed comparison if you can't be bothered reading through the translation. In the afterword of this novel, Shinkai notes that he started writing this novel when 5cm first premiered 2007 March in Shibuya and acts as a supplement to the movie.
Since then, there has also been a Manga version of the movie which I haven't had a read yet. Other 5cm fans say there is new material in there too but maybe it's just the same as the novel. There has also been another novel appropriately named as "One More Side" where a different author (under the supervision of Shinkai) takes a different approach to 5cm - mostly from Akari's perspective instead of Takaki's.
500 of you have said you want to see an official English version since the launch of my site. It might be worth asking Shinkai on Twitter about this too if you have an account.
Anyway, Takaki's back story can get pretty depressing in the novel so don't expect a heart-warming Christmas story!
Aside from that... Enjoy and happy holidays! =)
20th June 2013 Update:
The site has now been taken down but you may still get most of the content including the translations in PDF here.