I got my invitation to order months ago, but I was going to wait for the base model. However, once realized I was going to miss out on the tax credit if I waited I decided to get the LR. That said, I would have had my car in April or May, so the reservation did in fact put me ahead of almost everyone aka I don't think I wasted my $1000. Besides, the interest on $1K is barely worth noting in today's banking situation and it does get applied to your balance.
Oh and just side a note: This car FAR exceeded my expectations. It's simply amazing. I was very concerned I wouldn't be happy after sending so much money and time waiting, but it is by far the best car I've ever owned. I'm sure the base model will be well worth waiting for as well.