The way I see it, WordPress has it’s ups and downs. If you just want to blog and get some quick thoughts up, it’s easy, and the way to go.
Oh, but the theme business is a business. When you set up a WordPress site on WordPress.com, you have to choose a “theme.” A theme controls the look and feel of your site, and allows customization. So it’s cool with a click of a mouse you can change the theme of your site and therefore the whole appearance, and to some degree, how it behaves.

Now here’s the rub. All the “good” themes cost money. Big money.

Now here’s the rub. All the “good” themes cost money. Big money. We’re talking in the $60 range, a lot for your little blog. Or you can opt for a premium membership for $10 a month, wherein the themes are free, but in a year you’re paying $120, which is twice what the theme cost in the first place.
So for now, I’m sticking with the crappy little free themes they have. And if you see this site change from time to time, it’s because I probably changed the theme.