Okay, Let me start off by saying I don't have sex scenes in my books. I have tension building intimate scenes, but not full graphic sex scenes. However, I found an article at:
Perfect Sex - Or how to romance your reader, By Nina Pierce. I thought the article was great. Even if you aren't planning on writing a full sex scene, the notes on it are wonderful to help you remember what to do and what not to do in even just an intimate scene.
Use anatomy, not vague nonsensical pseudonyms for things that pull people out of the story. Remember to use all of the senses. And especially remember to use feelings. All those elements will help pull people into the romance and believe it. Also, there has to be vulnerability and walls broken down when scenes are played out between the main love interests.
Those items in the article, I found especially helpful! I plan to keep this article on file so that I can refer to it often when reviewing my intimate moments between characters. To make sure my romance is on the right track.
Thanx Nina Pierce for a great article!