I've always thought I preferred an exact date, to know exactly when everything was going to go down (slight control freak tendencies here). But I'm finding--as I wait, now, for some very important news that has no exact date--that it's actually easier for me when I don't know when I'll get whatever I'm waiting for.
I think this is because so often even when you have an exact date, the thing doesn't actually arrive then. It also means that most of the anxiety and/or anticipation about it is focused on that one day, rather than spread out over several. When I think I'm going to get something on That Day, then all the days leading up to then are still kind of anxious ('omigod! only three more days until ___!'), and then on That Day it completely takes over my brain ('is it here now? how about now?'), and if it doesn't come on That Day the days afterward are filled with panic and woe ('why hasn't it come? does that mean it's not coming at all? did some horrible problem delay it?').
I could be like that right now. But instead, because I have no specific date, I'm pretty zen. Sure, the news could come in three minutes. It could also come in three weeks. It's almost impossible for it to be late!
Of course, if enough time goes by that some unconscious internal deadline for getting-the-news passes, the panic will set in all the same. But I think I have a much better chance of avoiding it this way. :D
So, how do you prefer to wait?