Yes Tsappcmd.dll will affect any and all programs that do not have the TSAWARE flag in the PE header. This does NOT automatically mean however that all those apps are affected by this particular bug. But you can easily test this by setting the TSAWARE flag (see the link that TOndrej provided to my blog) or by setting the registry key that is mentioned in the KB article.
PS: the explanation that it's a protection against viruses seems like a bogus explanation, this mechanism was introduced for app compat reasons...
