I think that jelpee is saying that there's a difference between "Good" and "Good Enough", and while some people "pixel-peep" by critiquing their efforts by examining their photos at 100% magnification, or print hevily cropped images at 20x24, for the vast majority, superzoom lenses are good enough.
My first dSLR lens was the Tamron 18-200. I bought it becasue I though it could do everything. I was wrong. I quickly recognized and didn't like the softness or the distortion or the chromatic aberration. When I look at the test reports from SLRGear.com and PhotoZone.de, I see in their tables and charts exactly what I saw in my images (without pixel-peeping.) Newer superzoom lenses have gotten better, but they're still not as good as a combination of less expensive lenses that you'll have to switch occasionally.
And, btw, images posted here are resized, and here's a topic on
Why a resized photo is no use in showing camera quality