How does this actually help ?? Why would I want feeds based on my personal search history term ?

http://www.google.com/support/bin/answer.py?answer=38344&query=RSS&topic=0&type=f

Well, I have search history on my google home page. I just click on it when I'm trying to find something I previously searched for. Just a way to access your search history without having to go to the main search history site.

Otherwise, no use, but they aren't pushing this feature, it's just there for those who want to use it.

I would say that an RSS feed is a simpler way of implementing an API for search history. So for example, if someone wanted to store or perform statistics on their search history they could set up their script to read the RSS feed rather than a full blown complicated API that just gives a set of search terms.