As far as Opera goes though, you both have a point. If you really want to drill down into the data then your argument stands but generally speaking, without being oh so concerned and preoccupied with complete and totally accuracy (like we often are on HN and miss the forest for the trees because of) Opera really isn't much to worry about. It's a great browser and all but you can bet that if you're building a new web property you're not going to see a lot of Opera users with 1.6% market share worldwide. Sure, you might get lucky (or unlucky depending on how you see it) and somehow get a swarm of Opera users but I also might win the lottery this week too.