Now that the holidays have come and gone, many of the girls no longer look like that -- so they have to go back to last Summer to find some good pics. Plus it's not lingerie -- it's swimwear -- so to them it's more wholesome.

In keeping with their HUGE effort to separate from, and avoid being perceived as, an escort site, they do everything they can to emphasize the "meet for dating" concept and avoid the "meet to fuck" model.  
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This includes guidance that pics posted can not contain nudity (no nips, no pubic areas) and must not be overtly suggestive (i.e.: No pics of a SB with a rubber cock in her mouth).  
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My experience is that pics generally fall into 3 categories, probably based on the owners' goals:  
1. Protect privacy/avoid being recognized.
2. Appear as an attractive, non-slut (i.e.: be classy) to attract rich guys (who will be happy to "date" them in public).  
3. Try to get as close to overtly sexual/nude as possible, to attract rich guys (who just want to fuck a hot chick).  
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The pros or semi-pros tend to be category 3.  But to your point, in the last 2 months, I have seen more of the category 2 pics sliding closer to category 3.  
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There's another aspect to pics that crosses all categories that bears some discussion; pics of the SB in some glamorous locations, or doing something that requires big money (not HER money!) to do. Examples are pics on a yacht, outside exclusive restaurants & clubs, in front of a $200k car, sporting high-dollar designer crap (sun glasses, shoes, purses, etc.), or flying 1st class. All of these, IMO, are red flags of GPS. I have no interest in buying $2,000 shoes for an SB. I do have interest in helping her make her $900/month rent.  
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So a pic of a spinner in a bikini at her apartment pool - Nice.  
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A pic of a spinner in a bikini in the Infinity Pool at the top of the Sands Hotel in Singapore - not so much.  Yes, I've been in that pool and I know what it costs to be there. Not to mention ultra-hot spinner pros are all over Singapore for about $100 for 2 hours of PSE.  
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So to answer your original question, I think you need to put as much consideration into the whole context of a pic, as you do the subject.  You can infer a lot from what's in the pic, besides the SB.  
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Life is good.
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The Cat

It's become the norm.