If you don't have the specs to run MapsGL you can check out this feature run-down video
By now, you may have already noticed the WebGL experiment within Google Maps. Google has released a beta version of a rather ambitious plan to switch Google Maps to the 3D graphics technology.There are some caveats, you can read more about them here, but when and if it works, the technology is quite impressive. Moving about the map is much smoother, 3D buildings are actually 3D, you can use Street View without Flash and so on.
There are plenty of things to like about MapsGL. However, Google notes that this is just beta technology and it's not committing to any deadline for rolling this out to everyone.
So, if you're one of the unlucky ones that can't run MapsGL, and there are quite a few of you, you can at least check out this Google video showcasing what you're missing out on.