Are you tired using Google Earth? Maybe you should try something new?
Yes, then we’ve find a replacement for Google Earth! You can now check it out online!

Flash Earth , developed Paul Neave may work out for you. This one is like Google Earth but no download is required as it runs online.
This is compatible with firefox but you must have Adobe Flash Player seven installed in your computer before you try it on.
Not exactly like Google Earth and has not got many features like the Google’s but is alright as this is a online program.

This application contains several mapping services, including NASA, OpenAerialMap, OpenLayers, Microsoft Virtual Earth, Microsoft VE (labels), Yahoo! Maps and Ask.com Maps.
You also have access to controls like Zooming in or out , moving location directly from your browser. If you feel like Trying it out you may like to visit it at flash earth