Facebook have just announced they are going to stop supporting Internet Explorer 6. What about you? Do you intend to continue supporting it?
IE6 may only have 5% of the market, but a lot of those users are concentrated in the business sector where many corporate IT departments will only support IE6. (the same applies for UK Government departments).
And therein lies a dilemma. Stop supporting IE6 and you lose out on potential business customers. Continue to support IE6 and you may be incurring significant web development costs just to make your website accessible to a small percentage of your users.