Mine is self-hosted using wordpress.It works, but I am always tempted to write my own just because I want more control over the app. The templates that use widgets are nice and wordpress has a lot of nice plugins, but it just isn't the same. I used blogger a couple years ago and didn't like it much. That being said I would have to agree with andr that if it was not a personal blog and my startups blog I would host it elsewhere. You want someplace where you have some sort of communication with your users about what is going on in the event of the site going down. Oh I also have a tumblr account but don't really use it for blogging. I just wanted to check out the features. For the most part it is pretty cool and I could see where a really nice microblogging solution could be built off of something similar.