Millions of people who blog don’t want to deal with hosting their blog themselves, so they use a blogging service instead. There are many things that factor into the choice of blogging service, but one of them should always be site reliability. After all, if people can’t access your blog, it won’t get read.
Though services like Blogger, WordPress.com, and TypePad don’t give you as much control over your blog as you would have hosting it on your own (paid) hosting account, their uptime is quite impressive.
Pingdom did a recent test, over four months, to determine the reliability of various “instant blog” solutions. WordPress.com, Blogger, and TypePad all had no more than twenty minutes of total downtime. Some of the other services (which were polled every minute for the duration of the test) didn’t fare so well. Blog.com had over a day of downtime. Vox and LiveJournal were a bit excessive too, though their problem periods weren’t so excessive.
Not bad considering most of the services are free, or have free plans. They’re certainly a good option for smaller blogs, as they’re more stable than a lot of cheap shared hosting providers. (And you won’t be cut off for using “excessive CPU resources.”)