Depends on the shop. When I went to order a tri bike (a Cevelo P3), I had to buy it sight/size unseen. Once they ordered it, I was obligated to purchase it. I'm thankful it worked out for me. There was another bike I really wanted, but really wasn't sure I would like it, and at this LBS they also required you to buy the bike if they ordered it (so I didn't on this occasion). It can be scary ordering a bike you've never ridden. The bike I bought size unseen they did EXTENSIVE measurements with me so I was certain it would fit (and I had bought my previous 2 bikes from them so I trusted them).

Exciting about getting a new bike, tho, isn't it?