Which open-source vendors can afford the cloud?

CNet - Matt Asay - Cost and quality are two driving factors for open source's role as the bedrock for public cloud computing. Google, Amazon, and other public cloud providers simply can't compete with expensive, proprietary license-burdened infrastructure. They need open source. As cloud computing matures and moves from public to private clouds, however, we may see enterprises flock to free (as in cost) and open (as in freedom) infrastructure, too. What would this mean for subscription-based open-source vendors?