Bing comes as a search provider like other search engine providers and getting good response. Remember Bing is in Beta and will be live in few days. This add-in is available for both Internet explorer and Mozilla Firefox, you can get it from IE add-ons site and Mozilla Add-ons site respectively.
Bing for Windows 7?
Yes, Bing is available for Windows 7 as well. Get the installer from here named bing.osdx and install it.