I got my iMac in August of 2011. Since that time, other than having them update the OS to Lion I've added an additional 4 mess of memory to it for a total of 8. I'm not unhappy with the performance of the machine. My question is should I upgrade the OS or is this thing getting to its last leg, and possibly in need of replacement? I'm getting the spinning beach ball more often than I'd like, and some websites are telling me that my version of Safari is no longer supported. Looking for input, so feel free to let me know what you think. All comments welcomed. Thanks in advance.