My opinion on this manga is similar to what I would feel like if I heard that Christopher Nolan was going to put the Joker in his third Batman movie. I mean, it is already been done, and done almost to perfection. Why mess with it? There is pretty much no way to improve on it, anything else is just going to be a disappointment.
I guess I wouldn't be too upset if they tried to distance themselves from the movie as much as possible. An adaption of the novel might not be bad, for instance, so long as it doesn't try to copy Shinkai. An alternate viewpoint or something would be okay, I guess.
To be honest, I think that even if the DVD got a reprint, I wouldn't buy it unless it was available on BRD, which is something that is even less likely. This is definitely a movie that deserves to be seen in 1080p. Luckily, North America is in the same region as Japan for BRDs (Region A), and 5cm/s is definitely a movie that I am totally willing and prepared to pay loljapan prices for.
Let me know if you ever do find it. That just might be the movie that convinces me to finally buy a Blu-ray player.