Indeed, it seems that way after reading through it again and inserting a dot.

I would still argue that images used in the layout of the average site, most of which are already prone to having transparent parts, are better off using a lossless rather than a lossy format.

You're underestimating the number of non-photographic JPEG files in use despite lacking transparency. It appears a significant number of people don't care about artifacts.

That said, JPEG does today support lossless compression, if you really want to go there. It sort of even supports transparency[1].

[1] http://news.ycombinator.com/item?id=1772760 for a javascript solution; other approaches use container formats