I cloned my hard disk using Carbon Copy Cloner this past Saturday then backed up my key files and folders today to an external FireWire hard disk. Then this afternoon I simply upgraded my Mac OS X system from version 10.1.5 to 10.2 (codenamed "Jaguar"). The process couldn't have been easier and went very smoothly. After the initial setup which involved clicking half a dozen or so buttons and options (I opted for the equivalent of a "Clean Install"), the only other user involvement was to insert the second CD. The entire upgrade took about an hour to complete without any "hiccups" whatsoever. The new system definitely feels snappier! I expect to be madly updating software over the next week for maximum compatibility.