Not sure if TS 6.5 has the support built in for IE 8.
We used TS 6.5, IE6 for developing. But In production we got some issues related to the incompatibility of IE 8 with TS 6.5 from customers.One of the issue is 1)we create hyperlinks in the Visual editor something like giving relative path of a page that reside on our server. But on previewing its appending "about:" text instead of the "http:" infront of the link. So when we click the link its showing the error page not found. You can find it in editor, on opening the dcr back.
anyone else who can testify that IE8 with TS 6.7.2 (no SP, SP1, SP2, ... please be explicit) is working ok?thanks