Are they simply an indication that a provider saw you and believes you;re OK? Or do they include something like a "review" of the hobbyist?
As they can only be accessed by providers I can't look into them myself.

If you go to a member's Whitelist page you'll simply see a list of the women who've white listed them and the date on which they saw them.  It simply means they vouch for them as a good date.  But many gals don't even look at them and will not use them as a substitute for a direct recommendation or other screening.  They are helpful, but not as useful as a P411 listing with multiple "OKs."

Whitelists do not contain any actual information or notes in the way that a review does.  It could be like a "vouch" or "okay" or "recommendation", but it's my understanding that what constitutes a whitelist is somewhat subjective and varies from provider to provider.  One provider might Whitelist a client she has seen only once and found to be "okay", another provider might Whitelist only clients who she has seen many times and trusts to consistently be good clients over time.  I think this uncertainty is what makes it totally variable as to whether providers will accept Whitelist as a form of screening.  Some will, some won't, but ultimately in my opinion the whole "Whitelisting" process is a little too undefined to be particularly useful.  I do actually Whitelist clients who I have good experiences with, but I think seeing someone's Whitelists would only be one step in my screening process and I would require additional information in most cases, because that doesn't tell me much of anything.  Perhaps providers who "Whitelist" a client would be willing to provide a reference, however, and their names and links to their profiles being listed on a client's account page could help facilitate that process.  You also don't need VIP to view Whitelists, whereas you do need VIP to view a hobbyist's reviews.  So it's a slightly more public way of linking a hobbyist to certain providers.