We are working on it and this archive and house-cleaning effort is what will be released in beta form on the relaunched Piezography website.
Then these curves will be updated continually, (and dated with their creation dates). There are many hundreds of curves out there that need to be updated, renamed, organized, etc.
Long story short, try both curves and see what is best. The WN-SL curve was built to work with [I]both[/I] Warm Neutral and Sel (aka, it was validated on both machines). The NU curve is newer but was only built and validated on Neutral but the curves all work pretty well on all the different inksets.
We will publish a guide/schema to curve names.