Our ps3beta site has only ever supported the most modern browsers: IE8+, Firefox3+, Chrome4+, Safari4+ etc.
Whilst we made mention of this on the home page, if you landed on another page in the ps3beta site with an old browser, no mention was made of the need for a better browser, and the page was probably rendered incorrectly, and most definitely wouldn't have behaved properly either.
Now we do "browser sniffing" in a much more robust way. If you go to *any* page on the ps3beta site using an old browser, there is an unmissable message at the top of the page saying we only support modern browsers, and that the page below is probably broken.
Also, as our widgets are html-based, we do browser sniffing in them as well. If you embed a widget in your external website, and a user comes to your webpage in an old browser, then the widget won't display content, but rather a message saying why it can't.
In the future, we may support IE7, but we definitely won't be supporting IE6.