I'm really good at making "like it or not" decisions. I mean that if I'm in a store and see something I like, I know it immediately and waste no time walking right up to the register. I can spot a beautiful purse hiding under a mound of ugly ones, I can scan racks and hone in on THE piece or walk into a store and immediately know if its going to be a good one or not. This is a great skill to have...particularly for someone who likes shopping as much as I do.
Interestingly enough, I have a pretty identical experience on the web. Within a few seconds of a site loading, I scan the front page and give it a mental thumbs up or thumbs down. Generally, if its a shopping site and I've given it a mental thumbs down, unless they have something I REALLY want that no one else does, I'll just navigate away. Apparently I'm not the only one.
BBC News recently published a story about a study that indicates that our brains make a "like it or not" decision within a twentieth of a second after viewing a webpage.
Not that we all needed any additional reasons to snazz up our sites, but this certainly says a lot. For those that think the overall look of your site isn't that important to the success of your business, I say (with full on intensity and fervor) "You CRAZY."