I think it depends on the individuals, me personally, i dont want to get to deep into past relationships, right off the bat. But they do tend to come out, not usually from direct questioning, but in round about ways.
Initually, because you dont really know the person on that deep of a level yet, the feelings tend to be a bit more on the physical side. I wouldnt use the term cautious when i meet someone new, i look at it as a way of being respectful. If i meet someone that i am attracted to and hit it off with them, I dont want to give them the wrong impression, that i am only interested in them physically/sexually. Thats not to say that I wont kiss someone or fool around with someone, but i want to respect them as a person and let them know that i am not just in it for sex...that there may be something great on our hands.
When i was younger i would tend to rush into things much more quickly, thats not to say that those relationships wheren't meaningful or worthwhile, they were. But as i have gotten older I want to be a gentlemen and do what I feel is right...if we are really into each other, the time will come when we can express those feelings sexually. Hopefully, when that time comes we do understand each other on several levels, not just a physical one. I feel the results of those intimate times will be much more meaningful.
IC