Mac sluggish [spinning color wheel, slow overall performance] after Lion (Mac OSX 10.7) installation.
A problem with or an incomplete OSX installation.
Please, as always, backup your hard drive before preforming the following.
1.) Close all applications, Reboot the computer; hold down the shift key after the reboot (bong) sound. [Enters Macintosh Safe Boot]
2.) Run ‘Disk Utility’ located in the /Applications/Utilities folder.
3.) Select the “First Aid” tab in the top of the center window:
After completion, and if issues are found, Click “Repair Permissions”
8.) Reboot the computer, hopefully, the issues should be resolved.*
* If upon rebooting you are prompted the complete the Lion installation, do so as directed.