I have a Black MacBook from around 4 years ago, Intel Core 2 Duo 2.2, running Leopard. Of late it's been very slow, my browsers, Safari, Chrome and Firefox, all stop working after several hours of use, and the computer generally seems very laggy and washed up. So, for this, I come to you. Is it worth my while to buy the Snow Leopard upgrade and then get Lion, or is it probably just time for a new computer? I was hoping to get a new MBA when they get refreshed/redesigned next year, but I don't know if my patience will hold for that long. If I hear I'll get all kinds, or even some, of performance improvements by ditching Leopard, I'm willing to take that chance. Thanks in advance for your help, and happy holidays!