Eric Peterson thinks we're better off using Visits/Sessions as a way to compare sites than Unique Visitors; he's not focusing on pageviews because there's much bigger issues like Cookie Deletion, Visitors visiting during the same session in different browsers, etc.  Here's some excepts from Eric's post

"…Anyway, we can stop worrying about dying pages and dying page views now since the answer has been with us the whole time. It's not unique visitors … too many problems with how unique visitors are counted, what with cookie deletion and some of the inaccuracies ascribed to panel-based services. It's not time spent on site … the problems with this metric as the basis of comparison are many (connection speed, amount of content, quality of content, bathroom breaks, etc.)"

Actually, I look at visits to my blog more than any other number; but Visits/Sessions are treated very similar across different web analytics platforms - so even if it's not 100% accurate, it's better than comparing uniques or pageviews.