[instructions to enable the new Bing experience were removed]
Update 7/21/2011 8:23AM PST: I removed all magic cookie instructions, because it appears to have been causing a Search History privacy issue. In other words, everyone using the cookie appeared to be sharing Search History results. I strongly recommend you discontinue use of the cookie immediately. I’m expecting a nasty email from Bing any moment now.
Update 7/21/2011 12:07PM PST: I emailed the Bing team and it looks like they swiftly implemented a Search History “block”. Accessing the Search History via the previously reported cookie now results in the error: Your search history isn't available right now. Check back later.
Update 7/21/2011 1:32PM PST: Bing team tip: If you’d like Search History back, clear your cookies.