I own a blog about celebrities (mostly actors) originally started just for SEO purposes which suddenly took off on its own and is now doing slightly short of 500k pageviews per month. The good thing about the "entertainment" niche seems to be that you can get a lot of traffic. The bad thing is that I haven't found any way of monetizing on the traffic yet. I make "fuck all" from 500k a month traffic. I guess I could probably make around $500 from Adsense but I have been playing around with movie links through Amazon affiliate which has two problems: 1. low conversion rate and 2. low prices = low commission.
500k/month visitors in the right niche will make you shitloads. In this niche it hardly covers the server costs. But as I said, traffic seemed easy to drive. I get 95% from search engines without having done any real SEO at all.
Anyway, if you want, drop me a PM and I'll add a link to your site if you happen to have any movies by actors mentioned on my site.