Well, there are a few users complaining about the mouse skipping. My guess is that the problem is with the GPU. As I said already, while running Google Earth my RAM wasn't used completely, nor my CPU or my virtual memory. Anyway, if it's the graphic card, I'm very sure that Google will find a way to boost performance, I mean it's stupid that my Mac struggles even though there is over 500Mb of free and incatvie memory and 50% of CPU being used by the app. (Someone correct me if my technical conclusions are wrong 😛 )
Let's remember that this copy is leaked (even though it's all over the web and in MacUpdate). This is still a beta that shouldn't be public, I've seen a LOT of bugs already (tilt issues, route lines not complete, some features disabled, etc. just to name a few). So I'm very positive about Google making this app really polished before it's officially released.
Anyway, at 256x256 I can still have a lot of fun, this is probably the app that I've been waiting the most. Viewing the whole world from the top is just incredible. When I was a kid I saved some money and bought a poster of my home city form the space, and now with GE the whole earth is right in front of me.
This might be just a sneak peak of what we're going to see from Google in the next few years. 🙂