I should also say a word about consent. Body language and other implicit cues can only take you so far; before you hit the bedroom, you'd better make sure your partner is enthusiastic about the prospect, and that requires verbal communication.
If you said that verbal communication was one of the most effective ways to communicate enthusiastic consent, I would agree. But is it really required? That notion seems to counter-intuitive to me, because I can think up some ways to nonverbally communicate enthusiastic consent that don't seem ambiguous (to me). What if your partner tries something like the following:
I can understand the reluctance to admit nonverbal ways of communicating, since so many of those methods are indeed ambiguous. But saying that verbal communication is required seems to either miss out on the possibility of non-ambiguous nonverbal communication like the above, or be some sort of noble lie.
Okay, so it's not a fundamental necessity, but it's not a noble lie either; it's a matter of ethics. The consequences of misunderstanding, probabilistically weighted, are still serious enough that it's ethically better to maintain a habit of making a bit of sexy talk before hopping in bed with any new partner.
For the record, I have indeed misinterpreted what I thought were totally unambiguous "go" signals. Fortunately things did not progress far, but it was a big wake-up call for me.
Clarisse Thorn recently posted a useful article about Ethical Pick-Up Artistry, bringing up a few basic critiques of traditional PUA and suggesting a few alternatives.
A proposal to formalize thisNot the same thing, but a discussion on forming a community to practice social artistry in general has been brought up on LW before, but I'm not personally aware of anything coming out of that.