I was recently asked why I still stay on blogspot. It isn't from lack of knowledge, or opportunity. I admin 20 someodd other websites, and own several dozen domains.
It's because you can't DOS Google.
I get DOS'd a few times a year, and Google pretty much shrugs.
If I put my blog on my own hosting account, it'd hit bandwidth limits and get knocked offline a few times a year, causing me hassle and costing me money.
So, for now, I stay on Blogspot.