I did finally close my dreamhost account, it was to renew in January 2008. Contrary to how Netfirms is behaving, Dreamhost was amicable about the cancellation process. They produced a form, and asked why I was leaving. I said:

Consolidating my hosting in house, had some problems with your servers too, but overall it was OK.

After that, I entered my password, clicked cancel, and was done.