More ad dollars flowing into podcasting is generally seen as a good thing. Yet niche podcasters don’t see very much of it. Yes, there are “riches in the niches,” but only if your podcast is attractive enough. Yesterday, I shared the Vocalize service with you. It’s a nifty service that brand-based advertisers are going to love. As I was editing the episode, I started thinking about the need for podcasts of all sizes to make their shows more attractive to brand-based advertisers. …