There will always be deals in the future so buy now if you NEED it. Wait for the deal if you can hold off. The problem you'll face is that everyday you wait for the sale puts you one day closer to the rMini 2.
Yes, they will. There will be the usual holiday promotions that pop up, and they will be better deals than you'll find elsewhere.
However, if you want one, waiting around for said deal will not be worth it. The discount won't be substantial enough that you'd really regret it.
My method is to pro-rate my money spent over time used. If I have and am enjoying an rMini for a few months before it's discounted, I consider the money I didn't save to be even spread between the day I bought it and the day of the sale.