It's been a long time coming, but Windows Vista Release Candidate 1 is finally here. As Microsoft starts to collect feedback from a broad spectrum of users in one of its largest test programs ever, the company will soon be in a position to decide whether the product is solid enough to meet announced ship dates of November for enterprise customers and January 2007 for consumers. Earlier this week, I started using Vista build 5568, a version that Microsoft says should be virtually indistinguishable from the actual RC1 code. Since recent Vista revisions have been focusing on improving performance, compatibility,...