I totally disagree. I consider links here recommendations for good reading. If the discussion is not as in-depth as you might like, think of it as a set of informal reviews and opinions, probably more reliable than the ones on Amazon.
"Ask HN" threads are much more appropriate for book recommendations. Imagine if every book in the threads below were submitted- we'd have a bunch of noise and no real discussion.
Submissions like this are only useful for people too unmotivated to Google for "SICP".