WibbleWobble - 3:54 pm on May 14, 2003 (gmt 0)
The site that these stats come from is a major US brand, aimed at a very mainstream market.
This is clearly the defining factor, in my mind.
Its still the tech-savvy who use opera or moz variants; partly because they don't fret so much about upgrading or switching client, and partly because they know what they're doing. The simpler users are happy with whatever comes installed, and those are usually also the casual shoppers of mainstream sites. Over time this will undoubtedly change, though a little marketing from Opera wouldn't go amiss.