enigma1 - 2:13 pm on Nov 13, 2011 (gmt 0)
IMO for the time being serve HTML static content to all spiders. I do not expect them neither I want them to start messing with js. So in general I use jquery and ajax requests are basically invisible to spiders. There is no window.location if you view the html source or any other trace of js mangled with the html tags.
Also in the server logs which I check regularly there is no access trace of any spider to the js scripts. They do not access scripts so far and I do not expect this to change anytime soon. If a site uses ajax it doesn't mean it cannot serve static html if need be.
Now if you figured out a hole or a bug in a spider that perhaps boosts the seo one way or another by injecting js into the html in some way, let us know.