As a self confirmed conference junkie I speak at a dozen events each year, and attend many more. As such I've probably seen close to a thousand talks over the last five years. Because of this I've got a pretty good idea what makes for an exciting talk and how you can guarantee your session will suck.
As somebody who also organises two conferences, "UX London":http://uxlondon.com and "dConstruct":http://dconstruct.org I'm really keen on getting new talent into the speaking circuit while still maintaining quality. As such I've put together a quick guide to help both new and experienced speakers kick arse/ass.
Most of these tips aren't new, but you'll be surprised how few people actually follow them. However if you do, you'll be well on your way to being the next Jeff Veen, Jared Spool or Jason Santa Maria.