I certainly notice any time I boot something up that requires the JVM, I refuse to use the CLR, so I can't tell you much about my own experience with that.
As for page load times, this is silly. There is no startup time on a page at all. Possibly the first hit but there are warm start options for that in CLR at least which make this a complete non issue.
To give you an idea, 98% of our page hits are under 80ms processing time and we have big, heavy pages (we're old school asp.net mostly).
I'm talking about command-line applications, like the one in the article and in your first post. Then you get the startup every single time you run the command.