I've just come across this post by Richard Byrne in his Free Technology for Teachers Blog and I felt compelled to share it through my blog too as I think it's very clear and informative besides the fact that I'm a blogger too! Thanks Richard!
I'm sure you will draw your own conclusions after reading his post and table. I'd say it is rather straight forward as Blogger offers far more possibilities and options to you as a blogger, and the only fee incurred in would be if you wanted some custom domain mapping which sounds fair as it would require extra work.
I've been using Blogger since 2008 and my experience has been very positive. As you may have read at the top of the main page this blogging experience started as an experiment, grew and continues to grow as a personal repository of tools I come across, try and experiment with, and then mention here reporting on what I found out. I now have 19 followers and so I think it's no longer just a repository of tools I find but I somehow feel obliged to them - thank you so much for following my blog!
Ok, I'm sure you'll find Richard's post interesting and informative, and that if you want to get into blogging then that you go for Blogger!