Thanks for all the advice! He's a guitarist (a very very good one) and it's an indie/rock band. They play a few gigs and have some songs recorded and are generally ace. Everyone else in the band is non-JW and very 'normal', which I think is good. Music is possibly his greatest passion and it's one that I've supported him strongly in (I even run their website).
I imagine he's been living in limbo for quite a while, not sure why he hasn't fully committed to the society, or to you. He has to spend some time thinking about what he really wants.
That's exactly the impression I got. I asked him why he hadn't come to a conclusion yet and he said he finds it very difficult to think about. I want to help him with this, but I don't want to get in the way too much. I gathered that he really believes some facets of JW are true, but others are more doubtful, and he's also confused about why they have a book that talks about all the different religions in the world objectively (I can't remember the name of the book but I guess you all must know which one he means) but they also tell him not to talk to apostates.
I make a simple suggestion here; obtain a copy of a book called Crisis of Conscience, written by Raymond Franz a former member of the Governing Body of Jehovah's Witnesses in Brooklyn. Read it carefully, particularly the portions that deal with false reasoning and argumentation in the JW literature. Then give your BF a copy and ask him to read it too. By then, you are well informed on the religion and it's fallacies, and will be able to discuss it intelligently with him.
I really like the look of this book - I may have to get it soon. Thanks for the suggestion!
I'm going to back off talking to him about this until he's ready to bring it up himself - and in the meantime I will carry on doing my research. I'm really determined to help him see the truth. I love him very much and I'm not going to let him go so easily.