Be careful that you are not using any applications made for the Power PC. They will not work in Lion. Applications such as Office, Dreamweaver, some versions of Final cut will not work in Lion. You can check an application by starting it and then start the activity monitor. Find the app name and look across to see if it says intel or power PC. If it says power PC it will not work. There is no support foe Rosetta in Lion. So check out the applications you need before you upgrade. You will find the activity monitor in you utilities folder.
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