Newsstand apps use the same approval process as regular apps, there are no barriers to entry except figuring out how to code for Newsstand. Once you go Newsstand your "content" no longer needs to go through any Apple approval process. You just publish content any time you like, and a Newsstand App updates automatically. The only thing that needs to be approved is changes to your code. Overall though, Newsstand is not very well explained in Apple's documentation, and paid subscriptions are a mess.

We publish a standard app at the moment, because Baker did not support Newsstand until a short time ago. We will be updating in the next week or so.

DPS pricing is still bad. Single edition only gets you one issue. One freaking issue! You need to upgrade to professional ($495 per month!) or above to publish multiple issues, and then pay $.30 every time someone downloads one of your issues. Compare that to setting up Baker (free) and setting up Amazon S3 free account (15GB data out per month) and DPS looks like a total scam.