I found out about this yesterday and I was totally geeked. Then I found the competition for educators and thought I really need to give this a look. So I downloaded the latest version of Google Earth, and the new Ancient Rome layer wasn't there. It appeared sometime late yesterday.
This morning I downloaded it to give it a try and I am totally disappointed.
3D Ancient Rome suggests 2 GHz dual core processor with 3 GB RAM and a good video card with at least 512 ram. They don't list any minimum specs. My desktop computer couldn't hack it. It's running WinXP with a 2.8 GHz Pentium IV, 1 GB ram and an ok nVidia graphics card. As I started to load the data things started to crawl to the point of being totally useless.
So I decided to try my MacBook which has a 1.83 GHz dual core with 2 GB ram with Intel integrated graphics. It kind of worked, but not in any sort of satisfying way.
I was able to get the historic terrain with no real problems then I tried for the 250 Landmarks. This was slow and just barely doable. Then to prove to myself how inadequate my two year old computer is I decided to be silly and try for the 5000+ buildings. I watched for about five minutes as buildings were added at a rate of about maybe 5 a minute or so and decided I didn't have 1000+ minutes to wait for the rest of the buildings.
For me this is a bust. With just the landmark buildings in I could see that it could be really cool, but everything was a bit choppy and slow. I'm not sure I would be able to do an effective demo with this in class. And even if I could, with just the landmark buildings in place you don't get any sort of real sense for what ancient Rome looked like.
I have a feeling that the most important component needed to make this run is a good graphics card. The big prize for the educator competition is a new MacBook. The ironic part is that if the teacher can run the Ancient Rome layer they probably already have a pretty good, brand new laptop.