From 15,000 feet, the $2.5 million house at 123 Highland Drive in the Queen Anne district of Seattle doesn't look like much. The roof is a nondescript gray square; the yard, a tiny patch of fuzzy space. This doesn't bother Matt Bell, a 33-year-old sales executive in the market for a new home. He is focused on the numbers flickering at the bottom of the Web browser two feet in front of him, the constantly refreshed statistics such as average property value, county tax records, local schools, and previous selling prices. "Eh," he sighs. "It's $538 per square foot, but the neighborhood average is only $420." Opting not to leave a comment on the house's open blog, Bell abandons 123 Highland and zooms back out over the city, the neighborhood numbers blurring to keep up with him.