http://secunia.com/multiple_browsers_dialog_box_spoofing_test/ affected browsers: Konqueror Mozilla / Mozilla Firefox Opera Netscape Avant Browser Maxthon Safari http://secunia.com/multiple_browsers_form_field_focus_test/ affected browsers: Mozilla / Mozilla Firefox Netscape Avant Browser Maxthon
This sounds like a dup of an older bug.
No, it's a new one... In short, other tabs can open javascript dialogs whie you're looking at another tab, or watch keystrokes entered in their neighbour tabs. Since you can't force your victim to open your malicious site next to your super-secret banking site, you have to wait for them to do this... Not really exploitable... by itself.
seems low-risk to me.
closing this as wontfix.