Actually, the new chat features will work on Flash version 8 or higher.
And it has been tested on the following browsers:
IE (5, 6 and 7), Firefox (1 and 2), Opera (9.00), Netscape (8), AOL Explorer (1.5)
I haven't tested it on Safari, or any Mac clients yet.
The confusing bit is that some browsers are VERY stubborn about caching old versions of a flash movie, and refusing to download the new version from the Sleuth site.
Suggested fixes if new features don't work for you:
1) hold down CTRL-SHIFT and click the refresh button while on the chat page.
2) close all your browser windows. Then open one up and login again.
3) have your browser delete all your private/temporary files.
4) some combination of #2 and #3.
5) give up and wait a couple days. Most browsers will eventually desist and grab the latest chat client.