I haven't seen a lot of sessions at the 2007 Summit, but I did go through 4 or 5 across the week and I noticed a few things in all of them. There were some first time presenters, and some nervous ones as well, but even the experienced ones could do with a few tips. I'm not the best speaker, but there are a few things I'd recommend.

•  Don't read slides - This is the big one. We're all big people, many of us have the slides, and we don't need you to read them. Don't even read a bullet point if you're talking about it. Just assume we can read it and talk about what it means or the point you're making.
•  Speed - If 3 people have asked you questions and you say "I'll get to that later", you're moving too slow. I don't want you to talk fast, but you need to keep up the pace. It's better if we're overwhelmed in 75 minutes than underwhelmed.
•  Background - In line with speed, move quickly through background. We're all pros, we do this stuff and we want to hear about your idea. Don't spend too much time setting things up and do it quickly, 5-10 minutes. Practice this and if people are lost, they'll ask questions.
•  Focus - By this I mean the presentation should be focused. I saw a few presentations that were so broad, that they didn't really offer practical, sound advice. Too much information was presented, but it wasn't overwhelming, it was over load. Nothing was covered deeply. Focus your presentation on a problem. If you do lessons learned, do one every 10 minutes, mention the lesson and give some reasons behind it.
•  Repeat questions - Not just for us in the audience, but the audio recording as well. Repeat what you're asked.
•  Relax -  We want to like you. We think you've got a good idea or we wouldn't be there, so have confidence and relax.