This is a good overview of common configurations comparing nginx's syntax to apache's. Once you get used to it, I think nginx syntax is easier to understand, and it reads more like an actual script or program. I've been using nginx to host SoccerBlogs.net for 3 months now and its been very solid. In fact, it coupled with moving mysql to its own slice, forced me to focus some attention on SQL query bottlenecks.
Nginx has a major limitation in rewrite rules in that you cannot impose multiple conditions for a rewrite rule. Apache HTTPD on the other hand provides a good solution using multiple RewriteCond directives. Nginx on the other hand allows if statement. You can have rewrite rules within if blocks. However the if block themselves are limited. You do not have and or or to add multiple conditions to a single if block. Also you cannot nest if blocks. There are no else statement either. However you can use regular expressions so the following is possible: