There are a lot of benefits of combining the two blogs. First off – there’s only one design to work on and make changes to. Second, much easier to keep plugins and the WordPress install up-to-date. Only need to take care of this stuff once rather than twice.
If I decide to change the blog theme – I only need to do it in one place. And of course once I’m sure everything is working properly – I can turn off that second WordPress Install and cut the resources I’m using in half. I might even make this second blog into a sub-domain – something like blog.beckermanphoto.com
Not sure if there’s a benefit to a subdomain or not – but it feels a little bit neater (not that that’s my strong point).