Alt text for site skin previews

[fu]

We're adding some previews when you're choosing a site skin, and I've been thinking about an appropriate level of information for the alt text.

The alt text mentions the colors, the orientation of the menus, and whether or not the menus use Javascript. Is there anything else that needs to be added, or is there any non-essential information that should be removed?

For reference, here is sample alt text for four of the site skins:

Celerity

Olive and white with vertical non-Javascript menus

Gradation Horizontal

White on black with horizontal Javascript menus

Gradation Vertical

White on black with vertical non-Javascript menus

Lynx

Simple, bare skin with minimal decoration and navigation