I like the simplicity of sites like Twitterjobsearch or yours. You might want spice it a bit up with rounded corners, a gradient in the grey box. You can also try to transform your slogan to regular text instead of an image. The text in the image has sharp edges and you an easily replace it in _templates/YOUR_THEME/header.tpl.

I'm missing instructions on how to get to the jobs. Your forcing the user to use the search bar (with doesn't clear it's default value on click on the homepage), but you might want to consider adding a link to the categories or all jobs. Just for those who just want to browse for interesting jobs.

Cheers, Evert!

Edit: and you can use this (http://tools.dynamicdrive.com/favicon/) to create your own favicon (in the url bar) and replace Jobberbase deafult.