Blogging systems

There are so many blogging systems out there. I currently use Wordpress.com having used a privately hosted Wordpress site. I thought it would do everything I wanted but I've recently discovered that I can't embed any swf files such as Storybird or Aviary, hopefully that will change soon? I don't want to change again unless I can find out in advance what the pros and cons of the blogging system are. Does anyone know of a site that helps you to choose the right one or would like to comment here?