I've been to quite a few events and regardless of whether the speaker is good or bad i always pick up something from the speaker about how to portray yourself when public speaking (whether something not to do or something you should do) .

I always try and bring these learnings into play when i'm training groups of people looking to learn dba skills.

Not all of us DBA's are gifted with charisma, quick wit, or the ability to keep an audience enthralled - quite often we're stereotypically portrayed as sandal wearing beardy wierdies with no friends and the least popular person at a party compared to our more glamourous (and considerably worse paid) Game developers - but each to their own talent.

I've seen some excellent keynote speakers - anyone at dev 2008 last year would have loved Dave Wheeler's excellent keynote speech - but eaqually he was quite poor in a smaller lecture theater. Whereas Itzig Ben-gan, Fernando Heurrero (and most Solid Quality learnings people such as Michael Hotek) were excellent small audience speakers - although i can't imaging Itzig giving a keynote.

bizarrely enough - one of the worst speakers (at devcon 2005 i beleive) - is now editing the microsoft UK MSDN Flash newsletter......