Unfortunately we wont see an end to IE6 for a long time, it's a catch 22 TBH, IE6 is used by big companies, now Microsoft will not do an automatic update on the fear of annoying these big companies, and those big companies wont upgrade for downtime to the company.
So MPO is that every other browser could be state of the art, Firefox4 will change a lot of people opinions IMO and may push it as it has a lot of business area improvements, because the big companies know that by changing they are going to have down time, staff getting use to the new interface, if they don't use IE7 already at home, upgrading time on thousands of computers and paying someone to do it, when they already have a browser that works for what they want it to, using the net.
They don't need RSS feeds, add-ons, most big companies don't need 30 tabs open all at once, connection speeds I imagine are high, due to the amount of computers needed so again load times don't effect productivity that much.
So until browsers get business focused, like Firefox4 will, however that wont effect it that much TBH IMO, new interface massive learning curve, thus loss to productivity, IE6 will be here to stay TBH.