Promo codes appear to be functioning again, but there can be a longish delay when clicking the UPDATE button after entering the promo code.
Having said this; In my opinion, it might be a good idea to wait a while before signing up.
The recent reports of slowdowns across the DreamHost network are worrying. I personally am not seeing a dramatic slowdown on my sites, but there are enough reports from others to know that there is a very real problem at present.
I have no doubt that DreamHost will (sooner or later) take the required steps to rectify these problems and things will return to normal.
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