We feel it's critical that Internet Archive and Better World Books aren't the only organizations involved in determining which books should be preserved.
In late October, we launched a new program which allows anyone in the world to take control of our Library's shelves and contribute/sponsor the books which reflect their values: https://openlibrary.org/sponsorship
So far we've seen an influx of high quality reference books come in (everything from African antiquity to Microbial biology) that we almost certainly wouldn't have procured ourselves based solely on the data available from e.g. library holdings, wikipedia citations, etc.
Having Better World Books as a partner has been incredibly helpful because we're able to calculate sponsorship prices quite accuracy (because shipping prices are included) which was a big challenge with other APIs we previously used. Also importantly, Better World Books helps our patrons sponsor older books which are often more at risk of disappearing, which is one (of many) useful heuristics when considering preservation.