It's cute, but 'safer than a sofa' is part and parcel with the condescending marketing that isn't always effective. You don't cycle places? Well you must be fat and lazy.
I see what they're trying to do - combat the perception that cycling is dangerous while simultaneously pointing out its health benefits. However, I think the message comes out a little garbled.
Almost 40 percent of Copenhagen residents meet their minimum exercise requirements by cycling to work or school.
That's a lot more effective. Telling people that they can commute to work while simultaneously fulfilling the dreaded 'exercise requirement', all without having to don the spandex uniform... that's an effective message.
People naturally want to do the thing that's easier, so demonstrate how bicycle commuting can actually be easier in the end.