I like the concept, but think it would be better and make more as an ad-supported webapp. It looks too simple to be worth the time to download, scan for viruses, install and run on my already-cluttered desktop.

By the way, while I like the Einstein branding, be aware that his 'personality rights' (to use his name and/or likeness commercially) were bequeathed to an Israeli university and the licensing is administered by Corbis: http://einstein.biz/ You may want to consider a more generic or abstract image, rather than get hit with a substantial bill later if your product takes off.