I like guys to be different and interesting on dates. ok that's a bit vague, but i'll tell you what i don't like, guys who have prepared the whole date in their head! ie what they are going to say first, then which subject is a good idea to move on to,.. blah blah. don't rehearse! it's good when you end up talking about the strangest of things that you never thought you would on a first date. just see whatever comes up in conversation. it's annoying when conversation becomes mechanical and its obvious the guy is going through in his head what to say, what to avoid saying, a good thing to say when..., a bad thing to say when... etc. honestly, you will not make a fool out of yourself if you just forget all the things you must do and things you musn't, relax! girls really don't mind if you don't have a super-interesting topic up your sleeve.
oh, and silences don't need to be awkward. sometimes its nice to enjoy a comfortable companiable silence too. what makes a silence awkward is when one of you quickly tries to salvage the conversation by coming up with some crap just to have something to say. if you don't have anything good to say don't say anything at all, honestly its better. that way she doesn't have to respond to whatever crap you just said. crap can be good and funny too though.
finally, you don't need to come up with good subjects, just THINK OUT LOUD.
before anyone says that its hard for guys to be natural and they want to be prepare/listen to tips to feel more confident, i believe everyone has it in them to be a great chat, just let yourself go. forget the "rules".