Rated 5 out of 5 stars
Excellent search engine plugin, very useful ! A few improvement suggestions:
1. Encode icon as base64 - http://stackoverflow.com/questions/35879/base64-encoding-image
2. Current name is a bit long compared to the others. Maybe shortening as "timeanddate.com"
3. Might want to enable autoupdate - https://developer.mozilla.org/en/Creating_OpenSearch_plugins_for_Firefox
4. Correct its category within the AMO site. As of today appears in Thunderbird searches - https://addons.mozilla.org/en-US/thunderbird/search?q=&cat=all&as=true&vfuz=true&appid=18&lver=any&hver=any&atype=0&pid=0&lup=&pp=20&sort=newest