While the sites on BlogSpot and LiveJournal are predominantly personal blogs, Weblogs Inc. is a business that depends on advertising revenue. The network’s 75 niche-oriented blogs are now generating more than $1,000 a day in revenue from Google’s AdSense program alone, which comes to a halt when a site is offline and can’t display ads. “We’ve lost a couple of thousand dollars in advertising already thanks to the (hosting) problems,” Calcanis wrote in a March 28 blog post titled Yes, We Suck. “It is making me crazy.”

Weblogs Inc. is hosted at Logic Works/Digital Telemedia, a small New York provider serving about 2,700 hostnames. Many of the most popular weblogs are hosted by providers of modest size. The political blog DailyKos is hosted at Voxel.net in Troy, N.Y., while the Instapundit site lives at Hosting Matters/HMDNS in Jacksonville, Fla. And Boing Boing is hosted by Flarn.com, a niche host which houses 10 domains on a server at Priority Colo in Toronto.

Large web hosts are generally better equipped to handle manage huge volumes of traffic. But in the world of web hosting, even big hosts with sophisticated managed services are prone to periodic downtime. Nick Denton’s GawkerMedia stable of high profile blogs (Gawker, Wonkette, Gizmodo and Defamer) is hosted at The Planet, which houses more than 500,000 active sites. All the Gawker sites were offline for several hours late last month when power problems hit The Planet’s Dallas data center. The January LiveJournal outage was attributed to a power outage at Internap, apparently when someone mistakenly hit the data center’s emergency power off (EPO) button.

Netcraft measures hosting reliability for fifty leading hosting providers’ sites. The performance measurements are made at fifteen minute intervals from eight separate points around the internet, and averages are calculated over the immediately preceding 24 hour period.