I guess if you are looking to start a company that offers a free service that you try to monetize later, than ten million is the new one million. But if you start a company where users pay right off the bat, then perhaps you only need a few hundred customers. Sortfolio being the perfect example of an app that generated hundreds of thousands dollars/year, and took way less than one person to run.
For consumer startups with non-transactional models (ad-based or unknown business models), you need something closer to 10 million users versus 1 million users to get Series A funded. For consumer startups with transactional models, e.g. e-commerce, the number of users required is often far lower because revenue is the more important metric.
