It's a reference to the movie/book 2010: Odyssey Two, by Arther C. Clarke.

https://en.wikipedia.org/wiki/2010:_Odyssey_Two

I know the film sequel is shunned (and I presume rightfully so) but does the same apply about the book?

I’m probably not the best person to ask. I loved all four books and both movies. I actually saw 2010 before 2001 and dare say I kind of prefer 2010. 2001 is beautiful art but the pacing is slow. 2010 is a solid 80s sci-fi flick.

Slow is good, it's covering spans of millennia. This is not the book-endorsement I was looking for but I won't shun it either.

2010 will never be as good as 2001, but it is a really solid film. And it exonerates HAL in lovely form.