Here you can find a list of features that are included in the bundle upgrade: http://en.support.wordpress.com/bundles
We do have an advertising program called WordAds. Advertising outside of WordAds at WordPress.com is not allowed.
There are no restrictions if you setup a self-hosted WordPress.org blog instead of a WordPress.com blog, but there are some added responsibilities.
Please see this guide to learn about the differences. We have hosting recommendations at the following link if you are interested.