I couldn't imagine Dell (and others) NOT doing something special for the holidays; even if it's a coupon or "free shipping" sort of deal..
Also, the thing about waiting for prices to get bumped down:
In my opinion this happens for two reasons (basically) - 1) The product in question does not "move" well (i.e. low sales), and 2) New technology has come out to replace it.
Now, with those in mind, playing the "wait till it drops" game can be tricky. If it's #1 - there may be something really wrong with the machine; not always, but maybe. If it's #2, you would most likely have a small window of opportunity, as bigger companies like Dell typically don't keep the previous model around when the new one comes out.
However, the nice thing with Dell (well, it can be good or bad) is they have a large REFURBISHED section. This is where the real deals can be had, should you not mind a factory refurb. I know several people who went this route for both desktop PCs and Laptops - all were really happy and saved a TON of dough.
Good luck to ya,