My experience has been the opposite (though I don't for a second doubt yours): I've been surprised by a) how few things I missed having Flash for when I first started not having it and b) how many fewer things I miss it for in 2011 than when I first started not having it - it used to be that I felt like I couldn't watch video on the web on my iPhone... now when I hit a site that doesn't have HTML5 video I'm surprised (and think poorly of the site rather than of my device).
I don't think iOS shows the missing plugin box like it used to. It seems that now it just shows an empty box, which makes it look like you're seeing everything. Can someone confirm that they changed this on a software version at some point? It's my experience on the iPad. When I first got it I would run into 4 or 5 sites a day where I couldn't watch the video. I don't experience it as much now because I've trained myself not to follow links to videos at all unless it's YouTube.
