Even in cases where testing shows a borderline short-term "bang for the buck," there is an argument to be made for getting the upgrades now, if the cost from Apple is reasonable. For one recent example, the incremental performance gain between the base 1.8GHz Core i5 CPU and the upgraded 2.0GHz Core i7 processor in the new MacBook Air is relatively small. However, that $100 cost increase is also cheap insurance, just in case a future OS X upgrade requires the faster processor. Note that the recent OS X Mountain Lion release will not run on some Macs shipped less than four years ago, and while there are factors that may make this a special case, it is also entirely possible that this trend of shortened lifespan in terms of OS compatibility will continue. (If so, Apple will no doubt get an earful from unhappy customers).
Richard Hoffman is a technology analyst, IT strategist, systems architect and a former editor at several technology publications. He can be reached at Richard_Hoffman@me.com.
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