Since I'm not a gigging musician, looks shouldn't factor into the equation as much for me, but still they do. Like KingOfPain said above, I want to be 100% satisfied with my guitars. Looks are but one of many factors that go into a decision to buy a guitar, although it isn't the top priority. Tone rules all else, and then playability. But looks are right up there in importance for me.
I say this because I keep my Les Paul on a stand next to my rig in the basement. Every time I walk into the room, even 11 years after purchasing the guitar, I get a smile on my face. My LP makes me happy. I love its honeyburst, I love the cream pickguard. I love the shape, the Les Paul script logo, and I especially love the say it feels slung over my shoulder. It simply makes me happy.
And I find the same to be true about my Martin. It's such a beautiful guitar that I find myself just marveling at it. It makes me happy to look at it, its so astounding an instrument.
And what's even better about both of these instruments is that they sound incredible. I wouldn't own them otherwise. They make me happy when I look at them and they make me happy when I hear them.
So yeah, looks are pretty important to me I guess.