I haven’t heard of Photography Blogsites before so I don’t know much beyond what’s in their FAQ. It does look like they’re doing the grunt-work integration, which is probably worth the money if you’re not comfortable doing it yourself.

It’s not clear to me how customizable their sites are: I would bet they have an interface to tweak the colors, fonts, etc. but I get the sense that you don’t have the same degree of control that you would over a self-hosted WordPress installation. However, they do include maintenance, support, and updates (including security updates), and that’s big. 

It would be interesting to know if they’ve worked a hosting deal with Smugmug so your content isn’t coming from two totally different servers. That’s one big drawback of DIY’ing it.

I think what I would say generally is that if you’re relying on your site enough that any downtime would hurt clients or fans, and you’re not already pretty CSS and WordPress savvy, it’s probably worth paying for the service rather than learning as you go — there’s a lot that can go wrong. However, if you’re a hacker at heart who can take some time to really get a handle on the technologies underneath it and don’t mind being your own technical support, you would have a more flexible site.

I use a lot the pseudoclass :not(#none) quite a bit — as long as you’re not trying it on something with the #none ID, it’s a totally harmless way to get an element’s selectivity higher than Smugmug’s.

You are a life saver. :)