The payment structure is basically 70% to the seller, or the seller can pay a flat fee of $60/yr to become a "premium" seller and then keep 85% of sales. What's nice about their platform is that the customers are highly qualified and support is mostly offloaded to their support staff. When a customer makes a direct inquiry (to a seller like my wife) about a product there's a very high chance they will actually convert, so time answering questions is well-spent. If a customer wants a refund they contact TPT directly, so it can be a very hands-off kind of thing. We've discussed selling off-site to recover a piece of the 15% but it hardly seems worthwhile because of their infrastructure and how it allows her to focus on creating new products.
TPT has posted engineering job openings on HN in the past and seems like it'd be a great place to work in NYC if anyone is looking. I don't represent or know them personally but get a strong positive impression from their virtual meetings with sellers and people who I know who work closely with them.
As I understand it they have a bit of cross-pollination with the team at Etsy, which is another interesting marketplace similar to TPT but for arts & crafts products. You might know Etsy from their blog at codeascraft.com, presentations they openly host, or because Rasmus Lerdorf (creator of PHP) works there. If not, their blog is worth checking out.
