As I noted last month, blogging with WordPress has been a big time saver for me overall. There is one cost though, that every three or four weeks there is a security update to apply. I add this manually as I want to see what is going on and make sure my local copy is in sync with what is sitting on this website.
On balance, I think the power and flexibility of WordPress more than pays for the fact that it is a complex system and a big target for people hunting for exploits. A minor inconvenience but I can live with it.