That book was awesome. I just read Titan, and that one was not so much. A bit too depressing in my opinion. But Voyage is for any NASA nut.
I haven't read Titan, but I read the description and it looked pretty much like how you put it. Moonseed is also very depressing.
Voyage is kind of sad in it's own way, though, because it makes you think of what could have been. Of course, it seemed light-hearted to me because I didn't exactly look that way.
I've been reading Stephen Baxter's
Manifold series, I finished
Time not long ago and now I'm on
Space. He's pretty much my favorite author right now. Speaking of him, I started a group here for fans of his books.