Definitely this. I'm not even talking about being "an entertainer" - just have a little bit of spark, or personality. This is one of the reasons I enjoy Money to the Masses, even when some episodes don't have anything of value to me in the content - the two guys are obviously friends, having fun and enjoying what they do. On the opposite side of the spectrum, too much showmanship turns me off as well. Just don't be a know-it-all wanker! I guess it boils down to - if I feel you are being genuine, and talking to me as a (knowledgeable) friend would, that's cool.
I also like The Meaningful Money podcast, because Pete breaks his information into 2 sections - what you need to know, and what you need to do. Actionable advice (even if it seems simplistic) is important.
Finally, I don't want podcasts to go on for too long. I prefer half an hour, maximum. I've got too much variety that I want to listen to, and limited time. I have discarded some podcasts simply because at 1 hour an episode, I know I'd never be able to keep up.
Oh, one last pet peeve - please make sure the volume of your intros and outros (is that a word?) is level with the volume of your recorded podcast. The number of times I have to leap to the volume button because the podcast has ended and my ears are blasted by the closing music ... grrrr! I know nothing about sound post-production, but I'm sure there's equalisation or something that can be done, because it doesn't happen for every podcast I listen to.