I'm almost positive that the phonemag/engadget article has nothing to do with the HTC Dream. It looks like Engadget jumped the gun a bit. If you read the original phonemag article it makes no mention of HTC or the Dream. The article is just about showing off Android and its features. To add to this I think HTC would have made a much bigger deal about the Dream and it would have been all over the news already (why would Google show off HTC's phone?). Also that test phone looks exactly like the one in this video where they are just demoing Android.
http://www.youtube.com/watch?v=1FJHYqE0RDg