g1smd - 4:11 pm on Mar 3, 2012 (gmt 0)
alt="" would also be fine.
I recently wondered why the word "base" sometimes appeared in the snippet for some pages of a site I recently worked on. I soon noticed that this was the alt text for the image used as a border around the page footer navigation list. The
alt="base" now reads
Use lower case for atribute names and add quotes around the value.