"50 S of G" is terrible, yes. It's gushy and sloppy and improbable and trashy and train-wrecky. I'm pretty sure that's WHY it's so popular. It's the erotic-novel equivalent of "reality" TV.
People LOVE "reality" TV.
I know several very smart people in real life who watch VAST amounts of "reality" TV. It is not because they don't have a convenient list of better ways to squander their time, just as I do not reach for the spicy cheese-flavored tortilla chips due to any lack of proper food in the house.
I do enjoy the lists, though, and have idly contemplated making my own, though I don't expect any hypothetical mainstream ladies to start taking Georges Bataille's "Story of the Eye" to the beach as a result. It's a tricky algorithm to fiddle with, because succeeding as brilliant fiction and succeeding as hot dithering material are not necessarily that closely related. There's some kind of Venn Diagram here, and to each her own. Bad writing will throw me out of the spank-bubble, but really good writing can too.
Anyway... it is summer, it is tremendously and preposterously hot in DC, and I have received a sort of reviewer's copy of Tristan Taormino's ULTIMATE Guide to Kink (they need to find some way to make "ULTIMATE!!!" blink in different colors on the cover), so who knows, there may be further discussion of writing-about-sex in this space in the not-so-distant future. Comment with your favorite or least favorite books about or including sex, if you so desire.