I tried the N900 at the pre-launch party, here in Chicago, on November 2. To answer some questions of speed: this thing is fast. I had 9 windows/applications open (and minimized) and could swap between them without lag. Youtube was running as was another website that had some pretty heavy flash content. Facebook was running. The camera was in standby. The calendar was running. A twitter client was running. Google wave was running. A few other applications were running too.

You could minimize and see the thumbnails of all of the running apps and re-open any one of them. No pause, no gap. Pretty darn fast.

I cannot speak to Snapdragon. It is fast becoming my understanding that this is the beauty of a Linux OS. It is pretty compact and efficient and utilizes the RAM well.