I lifted this out of comments, because I thought it makes a good observation:

I find Jeremy's metrics to be rather poor. I followed those links and found, at best, a mixed bag in the responses. There was hardly the disdain that I've heard surrounding Vista. Some people are disappointed and from what I read, they are right in being so. Developers should have been given more time to deal with the changes. A lot of the troubles I hear about are a result of third-party apps.

So is the upshot this: Leopard issues are getting more play simply because the pie of Apple users has grown? The number of users is now large enough that third party issues - which once would have been a pretty small problem - are newsworthy now?