It's not as much the question if she should or should not testify in this case. It's rather: will or won't she be summoned to do so... If that were the case she wouldn't have much of a choice, now would she?
To be honest here: I never really cared much for Michael Jackson (sorry Elvisgirl ) but somehow I do have the feeling the guy's not as guilty as they're trying to make him look...
But hey, we'll have to wait and see, right?