There are a lot of factors that determine indexing. Here's a list: backlinks, visits by people in Google Chrome, links in Gmail, Google ad campaigns. There could be some creative ways that you could game this. We haven't really tried being too creative here; we've just done, you know, links and sitemap submission. But thinking about it, and again this is unproven, let's say I'd want to run some ads to get more Chrome user traffic.