Of course, you don't make the change if you don't want to become the B2B mega secure backup business that patrick is pitching. But if you do want to grow into that then you have to re-brand into something a clueless supervisor is going to be able to authorize. That won't happen often with the current design.
If Colin doesn't want to make a big B2B business, which I'm sure we all believe to be true, then you can keep the old design and be happy. But if he wants to have a "real" business, then he should absolutely go with a standard bootstap theme.
edit: four to for. duh