Wordpress.org or free wordpress.com, which would you choose?

If you want to start a blog which would you choose? Would you initially choose the free WordPress and then upgrade later on or would you prefer to get your own domain and use wordpress.org from the beginning so that you can customized everything and have full theme support? Is it wise to jumpstart your blogging career using free WordPress?

I would go with a self-hosted Wordpress (.org) for the reasons you stated since I would have more control over my own website (I can place my own ads and fully customise it). Overall, Wordpress.org can be the cheaper and more profitable option as well.